Monograph No. 51
NARA IMPERIAL PALACE SITE EXCAVATION REPORT XIV（1993）
RESEARCH REPORTS OF THE NARA NATIONAL CULTURAL PROPERTIES RESEARCH INSTITUTE, No. 51
(Volume commemorating the fortieth anniversary of the institute)
- Investigations into the Second Imperial Audience Hall Compound
English Table of Contents and Summary
Nara National Cultural Properties Research Institute (Nabunken)
1993
Table of Contents
Chapter I Introduction 1
A. Recent investigations into the Nara Imperial Palace 2
B. Protection and restoration of the Nara Imperial Palace site 3
C. Excavations prior to the restoration of the first imperial audience hall compound 5
D. Preparation of this site report 6
Chapter II Investigations 7
1. Excavated Areas 7
A. Location and its setting 7
B. Grid assignment and a compass direction 8
2. Summary of the Individual Investigations 10
A. First excavation of the Heijo investigations (1955) 10
B. 73rd excavation (1971) 11
C. 113rd excavation (1978-1979) 11
D. 132nd excavation (1981) 12
E. 152th and 153rd excavations (1983-1984) 12
3. Excavation Log 14
A. First excavation: Corridor of the imperial audience hall compound 14
B. 73rd excavation: Eastern pavilion (to-ro) 15
C. 113rd excavation: Imperial audience hall 16
D. 132nd excavation: Rear hall of the imperial audience hall 18
E. 152nd excavation: South gate (Ko-mon) and corridor 19
F. 153rd excavation: Corridor 22
Chapter III Site 25
1. Formation of the Site 25
A. Topography before the excavations 25
B. History of landscaping 26
2. Archaeological Features 28
A. Features dating to Phase I (ca. A.D. 710-746) 28
B. Features dating to Phase II (ca. 746-784) 33
C. Features of temporary structures 47
D. Other features 51
3. Shimeno Tumulus (middle fifth century burial mound) 54
A. Features 54
B. Reconstruction of the mound 59
Chapter IV Artifacts 61
1. Roof Tiles 61
A. Round eaves tiles 61
B. Flat eaves tiles 70
C. Round and flat roof tiles 78
D. Miscellaneous roof tiles (excluding eaves tiles) and tiles 81
E. Roof tiles and tiles with inscriptions 83
F. Eaves tiles dating to medieval and early modern periods 85
2. Pottery and Haniwa Clay Objects 86
A. Pottery dating to the eighth century and the beginning of the ninth century 86
B. Haniwa clay objects associated with the Shimeno Tumulus 87
C. Current state of the investigations into pottery discovered in the Nara Palace site 91
3. Stone and Metal Artifacts 93
A. Stone artifacts 93
B. Metal artifacts 93
4. Construction Materials 94
A. Pavement stones 94
B. Slabs used in facing palatial foundation platforms 94
C. Base course stones 94
Chapter V Discussion 96
1. Roof Tiles 96
A. Roof tiles associated with the Phase II features and their calendrical dates 96
B. Evidence of repairs and demolition in the Phase II features 117
C. Roof tiles associated with the Phase I features 121
D. Types of eaves tiles typologically related to round eaves tiles types 6225A, and 6225C, and flat eaves tiles 6663C 124
2. Archaeological Features 130
A. Archaeological features dating to Phase I 130
B. Archaeological features dating to Phase II 133
C. Archaeological features related to ceremonies and rituals 135
3. Plan of Building Layout 137
A. Plan and execution of building layout in Phase I 137
B. Plan and execution of building layout in Phase II 141
C. Plan and execution of other temporary structures 144
4. Nature of the Archaeological Features 145
A. Hypotheses concerning the second imperial audience hall 145
B. Nature of the Phase I features147
C. Palatial structures dating to Phase II 158
5. Examination of Historic Sources on the Imperial Audience Halls 171
A. Examples from the Nara Period (710-794) sources 171
B. Examples from the Heian Period (794-1185) sources 173
C. Palatial buildings where the emperor made appearances 175
6. Reconstruction of Buildings and Other Structures 179
A. Buildings and structures dating to Phase I 179
B. Buildings and structures dating to Phase II 179
Chapter VI Conclusion 183
A. Archaeological features 183
B. Functions of the imperial audience halls 184
C. Summary and conclusion 185
Chronology of events related to the Nara Palace
Wooden tablet inscriptions related to palatial buildings of the Nara Palace
Wooden tablet inscriptions mentioning the construction work of the Nara Palace (abridged)
Supplementary tables
English summary
Plans
Plates
Plans
1 Topography of the Nara Palace area
2 Map of all the archaeological features
3 Features of the Ko-mon (Phase II south gate) and the south gate in the lower stratum (Phase I)
4 Features of the imperial audience hall (Phase II) and the main hall of the Phase I compound in the lower stratum
5 Features of the rear hall of the imperial audience hall compound (Phase II) and the rear hall of the Phase I compound in the lower stratum
6 Phase II tamped earth wall
7 Lower stratum north-south fence
8 Eastern pavilion (Phase II compound)
9 Southeastern part of the corridor enclosing the Phase II compound
10 East side corridor enclosing the Phase II compound
11 Northeastern part of the corridor enclosing the Phase II compound
12 Eastern half of the south gate (Phase II) and the south side corridor enclosing the Phase II compound
13 Eastern half of the imperial audience hall (Phase II)
14 Eastern half of the rear hall (Phase II)
15 Western half of the south gate (Phase II)
16 Western half of the imperial audience hall (Phase II)
17 Western half of the rear hall (Phase II)
18 Northwestern corner of the corridor enclosing the Phase II compound
19 Phase II imperial audience hall compound: a reconstruction
20 Phase II imperial audience hall: a reconstruction
21 Phase II rear hall and the roofed corridor: a reconstruction
22 Phase II south gate and the corridor enclosing the compound: a reconstruction
23 Phase II eastern pavilion: a reconstruction
Plates
Frontispiece: Reconstructed roof of the second imperial audience hall
1 Second imperial audience hall compound area, aerial view from north
2 Second imperial audience hall compound
1 Phase II (ca. 746-784) features discovered during the 152nd and 153rd Heijo excavations, from southeast
2 Phase II features discovered during the 152nd and 153rd Heijo excavations, from northeast
3 Second imperial audience hall compound
1 Phase II features discovered during the 152nd and 153rd Heijo excavations, from west
2 Phase II features discovered during the 152nd Heijo excavation, from north
4 Second imperial audience hall (ca. 750-784) foundation platform (SB9150), from east
5 Second imperial audience hall foundation platform
1 General view, from west
2 Eastern half, from north
3 North side and a feature covered with pebbles (SX9145A), from north
6 Second imperial audience hall
1 Central part, from east
Nara Imperial Palace Site Excavation Report XIV
Investigations into the Second Imperial Audience Hall Compound
Summary
This report summarizes the results of excavations conducted in the second imperial audience hall compound (daigoku-den literally great supreme hall) of the Kara Imperial Palace (also referred to as the “Heijo Palace 平城宮” 710-784 A.D.), located in Kara City, Japan (see Fig. 99 for the location). The imperial audience hall, the most important place in the palace, was where the throne was located and where the emperor conducted important ceremonies and rituals, including his or her enthronement and New Year. This report covers sis seasons of the archaeological investigations carried out by the Kara National Cultural Properties Research Institute (hereafter Nabunken): in 1955 (First excavation of the Heijo Investigations), 1971 (73rd excavation), 1978-79 (113rd excavation), 1981 (132nd excavation), 1983 (152nd excavation), and 1983-84 (153rd excavation). These six seasons of archaeological fieldwork completely uncovered the eastern part of the second imperial audience hall compound, and clarified the arrangement of buildings in the compound, including the imperial audience hall, its rear hall (ko-den 後殿), south gate (Ko-mon 閤門), and the corridor enclosing the compound. Moreover, we discovered another set of buildings in the lower stratum of the compound, which indicated that a compound similar to the second imperial audience hall compound existed at the same time as the first imperial audience hall located to the west of the second imperial audience hall. The nature of the lower stratum compound is still subject to active discussion.
The excavations of the second imperial audience hall compound were expected to shed new light on the political history of eighth century Japan because of the political importance of imperial audience halls. For example, the shift in location of the imperial audience hall from being close to the imperial domicile (dairi 内裏, emperor’s residence) in the earlier Fujiwara Palace 藤原宮 (694-710) to being close to the state halls (chodo-in 朝堂院 where state affairs took place) in the later Heian Palace 平安宮 (794-1185) can be interpreted as symbolizing the move away from the dictatorship of the emperor to parliamentary government by the aristocracy 1. The absence of a south gate to the compound and the south side corridor of the imperial audience hall in the Heian Palace might indicate the increasing influence of Tang 唐 material culture because of its similarity to the Han’yuan Hall 含元殿 in the Tang Darning Palace 大明宮 in Chang’an 長安 (the present Xi’an) 2.
History of Research
The Nara Palace site and its imperial audience hall have long been a focus of historical and archaeological research 3. The site of the imperial audience hall particularly attracted attention because the foundation of the second imperial audience hall still remains on the ground as an earthen platform.
In the middle nineteenth century, referring to a map of the Heian Capital compiled in the fourteenth century and a map of the Nara Palace curated at the Saidai-ji 西大寺 temple in Nara, Kitaura Sadamasa 北浦定政, an officer of a local feudal fief near Nara, drew a hypothetically reconstructed map of the Nara Capital based on his field survey of the area of the Nara Capital, including the Nara Palace 4. His contribution became the basis for later research into the Nara Capital site. In his work, he recognized the earthen platform as the imperial audience hall of the Nara Palace.
Around the turn of the century, Sekino Tadashi 関野貞 conducted intensive research into the site based on Kitaura’s achievement and his own fieldwork 5. He attempted to reconstruct the imperial audience hall based on the Heian Palace model: His two major hypotheses were that, firstly, there was only one imperial audience hall as at other ancient palaces, and, secondly, that the south end of the imperial audience hall compound was not walled and instead the south end was a platform, like the Dragon Tail Platform (Ryubi-Dan 龍尾壇) of the Heian Palace (Fig. 2).
Sekino’s work led the national government to register the eastern half of the Palace area as a “historic site” in 1922. The government conducted some excavations prior to turning the site into a park. Having discovered a narrow platform-like feature to the south of the imperial audience hall foundation, Ueda Sampei 上田三平, the principal investigator, proposed a hypothesis that the imperial audience hall was walled on its south side, questioning Sekino’s hypothesis. However, the excavated area was so small that Ueda could not fully confirm the validity of his own hypothesis 6.
From December, 1953 to January, 1954, the Nara prefectural government conducted a rescue excavation under the direction of the national government, when a part of the imperial domicile corridor was discovered 7. The impact, of this excavation on the scholarly community was strong because the preservation was so good that three overlapping features could be distinguished, representing different chronological stages and also because the excavated area was located outside the presumed palace area. These factors necessitated the commencement of continuous investigations at the Kara Palace.
In 1955, Nabunken conducted its first excavation of the Heijo investigations from August 1 to August 20 in the area suspected to be the southeastern corner of the second imperial audience hall compound 8. Excavations in the 1950s were characterized by narrow trenches, which were very inefficient in comparison to current archaeological methods and techniques. This was one of the factors which prevented the discovery of the lower stratum features.
Nonetheless, the results of this first excavation were invaluable. It was confirmed that the current topography represented very well the archaeological features of the palatial structures of the eight century, and indicated the locations of individual palatial structures. The first excavation also clarified some unique features of the Nara Palace imperial audience hall compound in spite of the narrow excavated areas. The south end of the compound was indeed walled, thereby re-confirming the validity of Ueda’s hypothesis. Secondly, the imperial audience hall compound was located in an area slightly higher than the state halls, unlike the Fujiwara Palace where the imperial audience hall and the state halls were at the same level. These results allowed us to put the Nara Palace imperial audience hall into the context of the evolution of the imperial audience halls in Japanese ancient palaces.
Two further results of this excavation posed some problems with the idea that there was only one imperial audience hall at the Nara Palace. Firstly, none of the roof tiles discovered typologically belonged to the beginning of the eight century when the Nara Palace was constructed. Secondly, the imperial audience hall was not situated due north of the Scarlet Phoenix Gate (Suzaku-mon 朱雀門 south central gate). In that space was a large open area where the foundation of palatial walls still remained.
Accordingly, we hypothesized that the first imperial audience hall was first constructed in the center of the Palace. The structures of the first imperial audience hall were all transferred to the Kuni Palace 恭仁宮 imperial audience hall in southern Kyoto Prefecture in 740. When the palace was returned to Kara in 745, the second imperial audience hall was built in the currently designated area 9.
In the 1970s we excavated the first imperial audience hall several times. We discovered three strata of archaeological features (from the lowest to the top): the evidence of the first imperial audience hall which was indeed transferred to the Kuni Palace in southern Kyoto in 740; a complex of several large buildings dated to the Late Nara Period, which did not seem to have been related to the imperial audience hall; and structures related the residence of the Retired Emperor Heijo 平城 between 809 and 824 10.
In order to understand the second imperial audience hall compound itself and to see if lower stratum features existed, as they did at the site of the first imperial audience hall, we conducted four seasons of field work in the late 1970s and 1980s, the results of which are presented in this report. This report also contains the results of an excavation of the eastern pavilion (to-ro 東楼) located beyond the eastern corridor of the imperial audience hall 11;.
Features
The excavated units which altogether extend more than 16,000 sq. m were between the imperial domicile in the north and the second state halls compound in the south. The ground level of the second imperial audience hall compound was slightly lower than that of the imperial domicile and higher than the second state halls. In the second imperial audience hall compound, we discovered four strata of archaeological features. For dating these features, we rely on typological changes in eaves tiles, which are supported by stratigraphic context. We assign calendrical dates for each type of eaves tiles by their associations with artifacts with dated inscriptions 12.
A. Features older than the Nara Palace (prior to 710 A.D.)
We discovered a middle fifth century keyhole-shaped tumulus which was destroyed and leveled prior to the construction of the imperial domicile and the imperial audience hall compound. It was named the Shimeno Tumulus 神明野古墳. Its length was approximately 117 m, the diameter of the circular rear mound 65 m, and the width of the front mound 72 m. The tumulus was surrounded by a moat (Figs. 27, 28; Plates 51, 52). We also discovered some haniwa 埴輪 clay objects which originally stood on the surface of the mound (Figs. 42, 43; Plate 79).
B. Features in the Lower Stratum (Early Nara Period 710-ca. 746)
We discovered a complex of two buildings enclosed by fences with a gate to the south. All the buildings and fences were supported by columns directly planted into the ground, which are referred to as hottate-bashira 掘立柱 or post-hole type.
In the center of this compound was a main hall (SB9140). It was a seven by four bay building, approximately 30.9 X 17.7 m in plan. The space between two columns (i.e. one bay) was exactly 15 shaku 尺 13 (Fig. 7; Plate 38).
About 15 m behind this main hall was a rear hall (SB! 0050). It was a long, thin ten by two bay building oriented east-west, approximately 30.9 x 5.9m (Plate 39). A distinctive feature of this building is that its central axis runs through the two central north and south columns, rather than between the central bays. This feature is evident in very few other special cases, such as a building in the front courtyard of the imperial audience hall, used in the emperor’s enthronement ceremony.
The back wall of this building was connected to the fence (SA10051 and SAT0049) demarcating the north end of this complex. The fence was supported by a row of columns each of which were three meters (ten shaku) apart. It extended for approximately 71 m (240 tai-shaku) east-west (Plate 40-2). The three other sides of the complex were enclosed by the same type of fence (SA10048 for the east side and SA 11250 for the south end). The north-south length was approximately 80 m (270 tai-shaku) (Figs. 9, 10; Plate 40-1 and 4). This complex was further enclosed by another fence on the east side (SA7593) (Fig. 11; Plate 40-3) and probably on the unexcavated west side as well. A close relationship is suggested between this complex and the imperial domicile (710 to ca, 718) 14, which were connected by this outer fence.
Due south of the main hall was the south gate (SB 11210), marking the southern end of this complex. The south gate and the south fence (SA11250) stood on an earthen platform (Fig. 8; Plates 36, 37). Thus, this compound was identical in appearance to the south side of the first imperial audience hall compound which stood at the same time the west.
C. Features in the Upper Stratum (Late Nara Period ca. 746-ca. 784)
On the site of the above stood an entirely new complex of buildings, which is commonly referred to as the second imperial audience hall compound. All the permanent structures built in the Late Nara Period in this compound stood on base stones or soseki 礎石 which were all placed on raised foundation platforms. This new complex of buildings and the earlier complex shared the same central axis and so were closely related. The new complex was moved only 6 m (20 shaku) to the south.
1) Permanent buildings
The center of this complex was the second imperial audience hall (SB9150). It was a nine by four bay building with roofed verandas or hisashi 庇 15 on its four sides. Including the roofed verandas, it measured approximately 38.0 by 16 m. It stood on a foundation platform over 2.5 m high. The access to the platform was by stairs, three to the south, one each to the east and west, and two to the north (Plates 4, 5, 6, 8, 9, 10). There was a roofed corridor (SC9I44) for the access to the rear hall in the center of the north side rather than stairs.
On and around the platform we discovered two series of post-holes for scaffolding. One set of holes probably represented the scaffolding used for the construction of the imperial audience hall, and the other set represented that used for demolition of the imperial audience hall (Fig. 14).
We dissected the platform and revealed that the it was constructed by accumulating numerous layers between three and seven centimeters in thickness. Construction workers stamped each layer hard before piling on another layer. Before the placing of the base stones, a pit was dug and a few more layers of stamped earth added (Figs. 12. 13).
Approximately 10 m behind the second imperial audience hall was the rear hall (SB10000). Although the foundation platform of the rear hall was not well preserved, it was still possible to reconstruct it as a building of nine by two bays, 38.0 x 9.4 m. The rear hall and the imperial audience hall were connected by a corridor. The corridor was at the beginning of the Late Nara Period simply a 3.8 m wide platform, but later it w7as restructured as a 8.15 m wide roofed corridor, supported by two rows of columns, indicating it was a “single corridor” or tanro 単廊 (Plates 11-16).
The corridors which enclosed the imperial audience hall compound originated from this rear hall. These corridors are called “double or composite (fukuro 複廊)” and were elaborately constructed. Although a single structure, it was divided into two corridors by an earthen wall with windows. The whole structure was supported by three rows of columns. The east-west length of the corridor (including the length of the rear hall for the north side and of the south gate for the south side) was 118.0 m (24 bays). The north-south length was 84.9 m (23 bays) (Plates 20-19).
The south gate for the imperial audience hall was a structure of five bay by three bay, 22.1X8.9 m in plan. The entire structure stood on a platform of 2.5 to 2.7 m in height. In the center of the south side was a stairs of 13.2 m in width (Plates 17-19).
The eastern pavilion (to-ro, SB7700) was situated 83 m to the east of the second imperial audience hall. The western pavilion remains unexcavated, but was located symmetrically along the central axis of the imperial audience hall compound to the eastern pavilion. The eastern pavilion was sturdily constructed, having six by four bay structure supported by 40 columns on base stones. The dimension of the pavilion was 24.8 X 16.0 m. The whole structure stood on an earthen platform whose size measured 29x21 m, and 1.5 m in height (Plates 33, 34). Because of this heavy construction, we reconstruct the eastern pavilion as having at least two-stories. Since we did not excavate the lower stratum of the eastern pavilion, it remains uncertain whether it stood throughout the Nara Period (710 to 784) or another pavilion existed in the early Nara Period which was then replaced.
2) Temporary structures
In the upper stratum we discovered many features surrounding the second imperial audience hall, which were related to ceremonies and rituals conducted in the compound. Such features include a distinctive type of roofed veranda, six temporary stages, and seven flag poles. Through careful stratigraphic analyses of these overlapping features, it was possible to ascertain that these were built on four different occasions in the Late Nara Period, which are designated here as Phases a to d.
Phase a (ca. 746-770)
The roofed verandas were constructed on the north and south sides of the south gate. This type of veranda, called do-hisashi 土庇, were supported by columns directly planted into the ground rather than on base stones, and were temporarily installed for special or ceremonial occasions (Fig. 18). This discovery is significant because the existence of this type of veranda used to be known through a late ninth century painting of the Heian Palace (Fig.97).
Three meters to the south of the second imperial audience hall, we discovered a three-way corridor-like feature (SX11271). This structure shares the central axis with the second imperial audience hall. The function of this structure remains uncertain.
Phase b (ca. 770)
A north-south oriented corridor-like feature (SX11270) was installed in the front courtyard. This structure connects the central stairs of the second imperial audience hall and the south gate, so we suspect that this temporary corridor-like structure was used when the emperor made appearances in the south gate. Historic sources records that Emperors Junnin 淳仁 and Konin 光仁 made such appearances on the 25th day of the eleventh month, 758 (lunar calendar) and on the 23rd day of the eleventh month, 770 respectively. This feature was probably associated with the latter.
Phase c (ca. 770-781)
The roofed verandas (do-hisashi) installed on the south gate were replaced with smaller ones. In addition, six stages (SB11261-11266) were temporarily constructed in the front courtyard (Plates 45, 46). We also discovered similar evidence in the front courtyard of the first imperial audience hall. These stages were probably used for dances and music which historic sources record to have taken place in front of imperial audience halls.
Phase d (ca. 781)
Seven flag poles stood in the front courtyard (SX 11252-11258). According to the Engishiki [『延喜式』 Rules, codes, and ritual in the palace; complied in 927, effective in 967], at the New Year ceremonies and emperor’s enthronement ceremonies seven banners were displayed in the Heian Palace: in the center a banner with a copper crow, to the east banners with the sun, scarlet phoenix and blue dragons, and to the west banners with the moon, white tiger and black turtle. The Shoku-Nihon-gi [『続日本紀』 New Chronicle of Japan] also records that seven such banners were displayed at the New Year ceremony in 701 (lunar calendar) although the order of the banners was slightly altered. These seven flag poles were surrounded by numerous minor flag poles. The discovery of the evidence for these seven banners is very significant, providing that such a ceremony indeed Look place in the Nara Palace. We assume that these seven flag poles were used at the enthronement ceremony of Emperor Kammu 桓武 who later decided to move the capital to Nagaoka in 784 and then to Heian (present Kyoto) in 794 and who also formalized such ceremonies (Fig. 24; Plates 42, 43).
Approximately 10 m to the east and to the west of the imperial audience hall, we discovered a pair of north-south oriented buildings (SB10034), which are located symmetrically to each other along the central axis of the second imperial audience hall. They are five by four bay buildings, 15X12 m in plan. The columns of these two buildings were planted directly into the ground without base stones (Fig. 23). The functions of these buildings are unclear because no historic sources mention the existence, nor were any other imperial audience halls accompanied by similar buildings.
D. Features dated after the Nara Palace (809-824)
We only discovered two buildings which were related to the residence of Retired Emperor Heijo. One (SB11390) is in the middle of the east side corridor, and the other (SB9152) in the northwestern corner of the foundation platform of the second imperial audience hall. These two do not comprise a well planned palatial compound, unlike the case of the Western Palace (the top stratum of the first imperial audience hall compound) (Plates 48, 49),
Discussion: Significance of the Second Imperial Audience Hall Compound Excavations in the Light of the History of Ancient Palaces
Six excavations in the second imperial audience hall compound and the resultant discovery of a similar compound of buildings in the lower stratum indicate that the Nara Palace had two sets of palatial structures which could be considered as imperial audience halls 16. Taking into consideration the results of excavations not only in the first imperial audience hall compound area but also in the first and second state halls areas, we will give a tentative picture of the change in the central compounds of the Nara Palace from the early phase (up to 746) to the later phase (after 746). We also intend to consider the nature of these palatial compounds against this background of changes. Finally, we will put this change in the central compounds into the context of the history of ancient palaces from the Fujiwara Palace to the Heian Palace (See Fig. 100).
In the early Nara Period (ca. 710-746), the imperial audience hall existed in the area we designate as the first imperial audience hall compound, which is represented by the lower stratum features. This first imperial audience hall was in use until 740 when it was transferred to the Kuni Palace 17. To the south of this compound was the first state halls compound. This compound was an open space (a front courtyard) at the beginning of the Nara Period (ca. 710), but very long and thin structures oriented north-south were built around 720, which were used until the end of the Nara Period 18.
To the east, there were three palatial compounds: These were, from north to south, the imperial domicile 19; a compound of the post-hole type main hall and rear hall enclosed by fences (the lower stratum features of the second imperial audience hall compound), and another compound of probably twelve post-hole type buildings very similar to the upper stratum second state halls 20.
In the late Nara Period (ca. 746-784), the first state halls and imperial domicile continued to be used with some structural modifications. On the other hand, the first imperial audience hall compound was replaced by a group of large post-hole type buildings roofed with tree bark, which many researchers consider as the Western Palace (saigu 西宮). The new imperial audience hall was built to the south of the imperial domicile, and post-hole type buildings in the second state halls compounds were all replaced with heavy buildings on base stones.
In sum, the Nara Palace imperial audience hall moved from the western central complex to the eastern complex, and there were two sets of state hall compounds in the late Nara Period. However, whether the post-hole type palatial buildings in the lower stratum of the second imperial audience hall and the second state halls indeed represents an imperial audience hall and state halls remains to be debated 21. Some competing hypotheses concerning the interpretation of the lower stratum compound are that they were: the first imperial audience hall and first state halls; the front hall of the imperial domicile; or the palace of the crown prince who became the Emperor Shomu 聖武 (r. 724-749) for his political activities before his enthronement. The first hypothesis can be discounted because of the difference in the size with the imperial audience hall of the Kuni Palace. The second hypothesis is unlikely because the lower stratum compound seems more related to the state halls compound. The third is also difficult to accept because no other crown princes had their own palaces for political activities.
We propose that the imperial government in the early Nara Period utilized the first imperial audience hall and the main hall of the lower stratum (SB9140) according to ceremonies, which were classified into the three categories of “major,” “intermediate,” and “minor.” The major ceremonies included enthronement and New Year, and the intermediate ceremonies included imperial receptions for foreign guests. In other words, the emperor made appearances in the first imperial audience hall (SB7200) at the major and intermediate ceremonies, while appearing in the lower stratum main hall for the minor ceremonies.
In the late Nara Period when the Nara Palace only had one imperial audience hall (SB9150), most ceremonies were probably conducted there. At the same time, there were still two sets of state halls, indicating that some degree of functional specialization determining in which compounds they were performed must have continued.
We suspect that those who planned the Nara Palace learned such functional specialization of cercmonies from Chang’an, the capital of Tang. At the beginning of the Tang Dynasty (from 618 to middle seventh century) all the political activities and ceremonies took place in the Taiji Palace 太極宮 in the north central part of Chang’an. In 662, the Tang Emperor completely remodelled a detached villa located to the northeast of the Taiji Palace. This was the Darning Palace, in which the Han’yuan Hall was constructed in 663. Since then, while the most important ceremonies, such as imperial funerals and enthronements, took place in the Taiji Palace, the emperor conducted all the daily political activities in the Darning Palace. In other words, political importance moved from the Taiji Palace in the west to the Han’yuan Hall in the east. This locational shift of the political center was also the case in the Nara Palace.
More evidence that those who planned the Nara Palace had great knowledge about Chang’an was the similarity of palaces. The first imperial audience hall of the Nara Palace may have been modelled after the Han’yuan Hall of the Darning Palace, and the main halls of the Western Palace after the Linde Hall 麟徳殿 of the Darning Palace.
Our hypothesis explains why the Nara Palace had two central compounds, which was also the case in the Heian Palace where there were two sets of state halls (those to the south of the imperial audience hall and the Buraku-In 豊楽院 to the west of the former). Nonetheless, a problem remains that the Naniwa Palace (upeer statum; 723?-784) in Osaka and the Nagaoka Palace (784-794) in southwestern Kyoto only had a single set of central compound. This can be explained by the twin capital system, in which the Naniwa Palace was the secondary capital. While the primary capital, the Nara Palace, was equipped with two sets of state halls, the secondary capital only had one set. The number of state hall buildings differed, twelve for the Nara Capital as opposed to eight for the Naniwa Palace.
Although history records that the capital of Japan moved from Nara to Nagaoka in the eleventh month of 784 (lunar calendar), we argue that the Nagaoka Palace at the beginning was also a capital secondary to the Nara Palace. This hypothesis gains support from the evidence that all the structures, including roof tiles, were moved from the Naniwa Palace to the Nagaoka Palace, and that the size, number, and layout of the Nagaoka state halls were the same as at the Naniwa Palace.
In conclusion, the six excavations in the second imperial audience hall compound yielded significant results. We discovered another compound of palatial structures in the lower stratum, suggesting the possible presence of two sets of imperial audience halls and state halls. We also discovered a series of temporary structures in the upper stratum which were probably used for imperial ceremonies taking place in the second imperial audience hall compound. Because of the politically important position of the imperial audience halls in ancient palaces, the results of these excavations will greatly contribute to understanding the political history of eighth century Japan.
1 SAWAMURA Hitoshi. 1967. “Nara Jidai Izen no Kokyo [Ancient Capitals before the Nara Period].” Nihon no Kokogaku [Archaeology in Japan], Vol. 7 (Historic Period, Pt. 2), edited by MI KAMI Tsugio and NARASAKI Shoichi., Kawade Shobo, Tokyo, pp. 24-44.
2 KANO Ilisashi. 1975. “Ritsuryo Kokka to Toshi [Ritsuryo State and Cities].” Taikei Nikon Kokka-Shi [A History of Japanese State: an Outline], Vol. 1 (Ancient Period). University of Tokyo Press, Tokyo, pp. 219-254.; KITO Kiyoaki. 1978. “Nihon ni okeru Daigoku-den no Seiritsu [Origins of the Imperial Audience Halls in Japan.” Kodaishi Ronso (Collected essays in ancient Japanese history in celebration of Professor INOUE Mitsusada’s 60th birthday), Vol. 2., Yoshikawa-Kobunkan, Tokyo, pp 47-74; KANO Hisashi and KITO Kiyoaki. 1982. “Dai-1 -ji Daigoku-Den Chiku no Seikaku [Nature of the First Imperial Audience Hall Compound].” Heijo-Kyu Ato Hakkutsu Chosa Hokoku [Nara Imperial Palace Excavation Report], XI. (Research Reports of Nara National Cultural Properties Research Institute, No. 40), edited by MACHIDA Akira, Nara. pp, 225-235.
3 TSUBOI Kiyotari and TANAKA Migaku. 1991. The Historic City of Nara: an Archaeological Approach. The Centre for East Asian Cultural Studies, Tokyo and UNESCO, Paris, pp. 6-10.; MACHIDA Akira 1986. Heijo-Kyo [Heijo Capital]. New Science Co., Tokyo,. pp. 13-14.
4 KITAURA’s work has been reprinted and publishied in: 1976, Heijo-Kyu Ato Hozon no Senkaku-sha-tachi [Pioneers in the Preservation and Protection of the Nara Imperial Palace Site] Nara National Cultural Properties Research Institute, Kara.
5 SEKINO Tadashi. 1907. Heijo-Kyo oyobi Dai-dairi Ko [Consideration of the Nara Capital and its Imperial Domicile]. Memoirs of the Tokyo Imperial University (Engineering Section), Vol. 3, Tokyo.
6 UEDA Sampei. 1926. “Heijo-Kyu Shi Chosa Hokoku [Report of Investigations into the Nara Palace Site].” Shiseki Seisa Hokoku [Detailed Investigations into Historic Sites], Vol. 2, edited by the Ministry of Interior. Hakuho-sha. Tokyo, p. 41.
7 Agency for Cultural Affairs. 1957. Heijo-Kyu Ato - Chodo-In Hoppo Chiiki no Chosa [Nara Palace Site - Excavations of the Area to the North of State Halls]. Tokvo.
8 Staff of the Nara National Cultural Properties Research Institute. 1961. Heijo-Kyu A to, Den Asuka-Itabukinomiya A to Hakkutsu Chosa Hokoku. (Research Reports of the Nara National Cultural Properties Research Institute, No. 10). Nara. pp. 1-16.
9 Staff of the Nara National Cultural Properties Research Institute. 1962. Heijo-Kyu Ato Hakkutsu Chosa Hokoku II. (Research Reports of the Nara National Cultural Properties Research Institute, No. 15), Nara.
10 MACHIDA Akira, editor. 1982. Heijyo-Kyu Ato Hakkutsu Chosa Hokoku XI. (Research Reports of the Nara National Cultural Properties Research Institute, No. 40), Nara.
11 The purposes of individual excavations arc: 73rd (1971) to excavate the eastern pavillion; 113rd (1978-1979) to excavate the second imperial audience hall; 132nd (1981) to determine the plan of the imperial audience rear hall and its connection with the corridor demarcating the compound; 152nd and 153rd excavations (1983-1984) to trace the southern and eastern part of the corridor demarcating the compound and to determine the plan of the south gate to the compound.
12 MORIMITSU Toshihiko. 1991. “Heijo-kyu, Kyo Shutsudo Noki-gawara Hennen no Saikento [Re-examination of Chronology of the Eaves Tiles Excavated in the Nara Capital and Palace].” Heijo-Kyu Ato Hakkutsu Chosa Hokoku XIII. (Research Reports of the Nara National Cultural Properties Research Institute, No. 50), edited by MIYAMOTO Nagajiro and TATSUMI Jun’ichiro, Nara. pp.251-342.
13 A unit of length in premodern Japan, During the Nara Period, one taishaku equaled 0.354m. and one shaku equaled 0.259m.
14 See MIYAMOTO Nagajiro and TATSUMI Jun'ichiro, editors. 1991. Heijo-Kyu Ato Hakkutsu Chosa Hokoku XIII, (Research Reports of the Nara National Cultural Properties Research Institute, No. 50), Nara. See Figs. 87 and 88, both of which must be corrected; SA7608 on Fig. 87 does not exist, and in Fig. 88 SA7593 should have been drawn to the east of SA10048.
15 A hisashi is a narrow aisle-like area outside of the core (moya) of a building. Throughout the text it is referred to as a “roofed veranda.”
16 For this reason, the designations of the “first” and “second” compounds do not necessarily imply the chronological sucession from the first to the second. Accordingly, some researchers prefer using the designations of the “central” and “eastern” compounds. However, we use the conventional designations throughout the text of this report to avoid confusion over terminologies. See, for example:
ABE Gihei. 1973. “Heijo-Kyu no Dairi, Chugu, Saigu Ko [Considerasions on the Imperial Domicile, Empress’ Private Residence, and Western Palace of the Nara Palace].” Research Reports of the Nara National Cultural Properties Research Institute, No. 22; 1984. “Kodai Kyuto Chusu-bu no Hensen nitsuite [A Study of the Transformation of the Central Compounds of the Ancient Palaces].” Bulletin of the National Museum of Japanese History, Vol. 3, pp. 121-170.
17 MACHIDA Akira, editor. 1982. Heijo-Kyu A to Hakkutsu Chosa Hokoku XI. (Research Reports of the Nara National Cultural Properties Research Institute, No. 40), Nara.
18 Preliminary reports of excavations of the first state halls compound have been published in the following annual volumes of the Bulletin of the Nara National Cultural Properties Research Institute: 1977, p. 22; 1978, p. 19; 1979, p. 23; 1980, p. 25.
19 MIYAMOTO Nagajiro and TATSUMI Jun’ichiro, editors. 1991. Heijo-Kyu Ato Hakkutsu Chosa Hokoku XIII. (Research Reports of the Nara National Cultural Properties Research Institute, No. 50.), Nara.
20 Preliminary reports of excavations of the second state halls compound have been published in the following annual volumes of the Preliminary Reports of Excavations by the Division of the Nara Palace Site Investigations: 1984, pp. 20-38.; 1985, pp. 25-44.; 1986, pp. 3-10.; 1988, pp. 3-10.; 1989, pp. 17-24.; and 1991, pp. 3-19.
21 For detail see MACHIDA Akira. 1986. Heijo-Kyo [Heijo Capital], New Science Co., Tokyo, pp. 46-47.
Fig. 99 Locations of Nara Capital and other ancient capitals
Fig. 100 Evolution of the central compounds, including the imperial domicile, imperial audience hall, and state halls, in ancient palaces.
Fujiwara Palace (694-710) where the imperial audience hall and state halls were established as set for the first time; the central compound consisted of the imperial domicile, imperial audience hall, state halls, and imperial assembly halls organized from north to south along the central axis of the palace.
Nara (Heijo) Palace (710-784) which had two units of the central compound consisting of the imperial audience hall and state halls; (710-ca. 746) the imperial audience hall located due north of the Scarlet Phoenix Gate (south central gate), which was transferred to the Kuni Palace in 740; to the north of the secondary state halls was the imperial domicile, the main hall of which was probably called the Dai an Hall; (ca, 746-784) the new imperial audience hall built.
Heian Palace (794-1185): the basic layout of the central compound consisting of two units was adopted; the state halls compound to the south of the imperial audience hall was also called hassho-in (八省院 compound of eight ministry buildings), and the other state halls compound to the west of the first state halls compound was called Buraku-In.
1993年3月5日 発行
平城宮発掘調査報告 XIV
奈良国立文化財研究所創立40周年記念学報 第51冊
