Fortified castles on Okinawa Island during the Gusuku Period, AD 1200-1600.

Fortified castles on Okinawa Island during the Gusuku Period, AD 1200-1600. Introduction Fortified fortified (fôrt´fīd),adj containing additives more potent than the principal ingredient. castles on the island of Okinawa, southwestern Japan,date from approximately AD 1200 to 1600. These castles are termed gusukuin Okinawan dialect. The larger of these multifunctional sites usuallycontained a number of different activity areas (Pearson 1992; 1997;1999). Katsuren Castle, located on the east coast of Okinawa, is oneexample (FIGURE 1). Extensive excavation and restoration of the castle(Asato 1990) suggest that it was approximately 12,000 sq. m in size, andincluded four enclosures. The smallest, highest and most protectedenclosure was the sacred precinct. The second enclosure contained theresidential palace, and the third was an area in front of theresidential palace used for assemblies. The fourth, lowest enclosureincluded storage, a work place for artisans and a well. The largestcastles ranged from 38,000 to 43,000 sq. m (Pearson 1962: 268). [Figure 1 ILLUSTRATION OMITTED] Okinawan histories, such as the Chuzan Seikan (Haneiji 1983)written in the 17th century, describe competition for power throughoutthe island in the form of various confederacies until the emergence ofthree polities in the 14th century. These polities were located in thenorth, central region and south of the island, and they were unified bythe central polity, the Chuzan Kingdom, in AD 1429. Okinawan prefectural pre��fec��ture?n.1. The district administered or governed by a prefect.2. The office or authority of a prefect.3. The residence or housing of a prefect. archaeologists have located 192 gusuku sites (Okinawa Ken 1983), shownas circles, squares and triangles in FIGURE 2. All of these castles werebuilt within the period c. AD 1200-1554. By 1429 Shuri Castle Shuri Castle (Okinawan: sui ugusiku, Japanese: 首里城 Shurijō) is a gusuku (Ryūkyūan castle) in Shuri, Okinawa. It was the palace of the Ryūkyū Kingdom. was thecentre of the Chuzan Kingdom, and by 1554 only four specialized castlesthroughout the island were maintained (Pearson 1997: 126). In 1609 theChuzan Kingdom was invaded by the Satsuma Satsuma(säts`mä), peninsula, Kagoshima prefecture, SW Kyushu, Japan. It gives its name to a famous porcelain, Satsuma ware, which was first manufactured there by Korean artisans in fiefdom fief��dom?n.1. The estate or domain of a feudal lord.2. Something over which one dominant person or group exercises control: of southern Japan,which controlled it until 1879. It became known as the Ryukyu Kingdom. [Figure 2 ILLUSTRATION OMITTED] Asato (1990: 128-37; 1998) published a discussion of site groupingsand their distribution, and their development into 17th- and18th-century political divisions (magiri) and cultural subgroups. Basedon a non-statistical analysis, he traced the development of prehistoricshell-mound site groups, to subgroups sharing certain kinds of potterytemper, to castle groups and finally to administrative sub units at thetime of the Ryukyu Kingdom (AD 1609-1879). Our study parallels andextends his historical interpretation by using a geographicalinformation system Geographical Information System - Geographic Information System to analyse the distribution of fortified castles inrelation to each other and the soils of the island. Soils and subsistence activities During the first half of the 2nd millennium, subsistencecultivation on Okinawa was based on a combination of dry-field wheat(Triticum aestivum), barley (Hordeum vulgare Noun 1. Hordeum vulgare - grass yielding grain used for breakfast food and animal feed and in malt beveragescommon barleybarley, barleycorn - a grain of barleybarley - cultivated since prehistoric times; grown for forage and grain ), foxtail millet millet,common name for several species of grasses cultivated mainly for cereals in the Eastern Hemisphere and for forage and hay in North America. The principal varieties are the foxtail, pearl, and barnyard millets and the proso millet, called also broomcorn millet (Setariaitalica), broomcorn millet broomcorn milletsee panicummiliaceum. (Panicum miliaceum) and irrigated rice (Oryzasativa) (Sasaki 1973; Asato 1990). A preponderance of wheat, barley,foxtail millet and broomcorn millet in flotation samples analysed byTakamiya (1997) may indicate that dry-field farming was predominant;however, only two sites have been analysed and the samples arerelatively small. In addition, taro taro:see arum. taroHerbaceous plant (Colocasia esculenta) of the arum family, probably native to Southeast Asia and taken to the Pacific islands. was grown extensively in areas withadequate moisture (Sasaki 1973). Takamiya (1997) suggests that rice wasnot a primary crop on the island because it matures during the typhoon typhoon:see hurricane. season and could therefore be easily ruined. Chinzei et al. (1967) grouped the soils of Okinawa into five basictypes (podzolics, forest, alluvium al��lu��vi��um?n. pl. al��lu��vi��ums or al��lu��vi��aSediment deposited by flowing water, as in a riverbed, flood plain, or delta. Also called alluvion. , regosols and lithosols). We havemade a further subdivision within lithosols, and group the Okinawansoils into six types (see FIGURE 2). The reddish podzolics of centraland northern Okinawa are derived from metamorphosed sediments ofPalaeozoic Age, principally phyllites and feldspathic feld��spath��ic?adj.Of, relating to, or containing feldspar.[From obsolete German Feldspath, feldspar; see feldspar. sandstone. Thebrown forest soils are found primarily in the central region of theisland, and are derived from raised limestone coral. The alluvial soils,including gley gleySticky clay soil or soil layer formed under the surface of some waterlogged soils. Characteristic of poorly drained areas, gley soils contain reduced amounts of iron and other elements and are gray and mottled in colour. and immature gravelly grav��el��ly?adj.1. Of, full of, or covered with rock fragments or pebbles: a gravelly beach.2. Having a harsh rasping sound: a gravelly voice. and sandy soils, are found innarrow inland valleys and coastal flats throughout the island. Theregosols of southern Okinawa are azonal soils (without A and B horizons)that developed from deep unconsolidated deposits of marl-like rocks orsoft minerals with no genetic horizons. The lithosols consist ofrecently weathered rock fragments on steep slopes and are found in boththe north and south of the island. We distinguish the northern lithosolswhich are acidic and are derived from metamorphosed Palaeozoicsediments, and the southern lithosols which are neutral or alkalinesoils derived from raised limestone. In general the brown forest soils and deeper regosols would havebeen suitable for growing wheat and barley. Millet would have been grownin these deeper soils but also in the shallower southern lithosols. Themoisture-retentive alluvium would have been suitable for growing rice ordryland taro. Traditionally, slash-and-burn cultivation would have beenpractised on the relatively poor podzolics and northern lithosols, butproduction would have been quite low (Sasaki 1973). Analysis Our analysis suggests that the 192 castles are not distributedrandomly across the island. A chi-square statistic indicates that theyare differentially distributed with respect to the six different soiltypes (FIGURE 3). Given the relative proportions of the soils, there aresignificantly fewer castles then expected on the podzolics and northernlithosols, and far more than expected on the forest, regosols, alluviumand southern lithosols. Sites are comparatively fewer in the central andnorthern regions of Okinawa and their distribution is distinct from therest of the island. They are usually found near pockets of alluvium,with low densities of sites found in the large areas of northernlithosols and podzolics. [Figure 3 ILLUSTRATION OMITTED] Spatial clustering The pattern concerning the distribution of castles is clarified byconsidering the distances between the sites. The majority of the castlesare spaced at a relatively short distance from each other, atapproximately the same distance from their nearest neighbours. Theaverage distance between castles is 1.282 km with a standard deviationof 1.692. Despite this, there are a number of castles that arerelatively far from some of their nearest neighbours, and thus aclustering effect occurs. This is confirmed by a Clark-Evans nearestneighbour coefficient of -7.389, suggesting that there is a significantlevel of clustering in the distribution of the castles. A K-meansstatistic can be used to determine the number of clusters formed by theOkinawan castles. Kintigh & Ammerman (1982) and Blankholm (1990: 65)note that the optimum number of clusters in a geographic distribution isindicated by the inflection point Inflection PointAn event that changes the way we think and act.-Andy Grove, Founder of Intel.Notes:For example, the fall of the Berlin Wall was an inflection point in global politics and the commercialization of the Internet was an inflection point in technology. or points in a graph of the logpercent of the sum of the squared distances from each point within acluster to the centroid centroidIn geometry, the centre of mass of a two-dimensional figure or three-dimensional solid. Thus the centroid of a two-dimensional figure represents the point at which it could be balanced if it were cut out of, for example, sheet metal. of the cluster. This measure is referred to asthe log% SSE (1) An earlier full-screen editor in OS/2.(2) (Streaming SIMD Extensions) A series of additional instructions built into Pentium CPU chips for improved multimedia performance by performing mathematical operations on multiple sets of data at the value. When the rate of reduction of log%SSE values beginsto decline, thereby creating an inflection point, it is at this pointthat the optimum number of clusters occurs. FIGURE 4 includes a graph ofthe log%SSE values for the cluster configurations of all the castles onOkinawa. There is an inflection point on the graph at three clusters.The distribution of the castles assigned to each of the three clustersis shown in FIGURE 2. The castles form a northern group (n=34), acentral group (n=55), and a southern group (n-103). This clustering isto some extent the result of the linear shape of the island and thepresence of peninsulas in the northern, central, and southern areas. Inaddition, the avoidance of lithosols in the north and podzolics in themiddle of the island, creates natural buffers between the three clustersand a relatively barren region for agriculture in the far north of theisland. [Figure 4 ILLUSTRATION OMITTED] The three clusters generally correspond to the three competinghistorically known 14th-century polities of Sanhoku in the north, Chuzanin the central region and Sannan in the south. There is, however, aninteresting discrepancy between the clustering and the historicallyknown distribution of the three polities. The statistical boundarybetween the southern and central cluster is located too far south. Thecastles of Urasoe and Shuri are included in the southern cluster, buthistorically these two sites were part of the central Chuzan polity.Historically, the Chuzan polity had strong links to the southeasternpart of the island. Soil catchments Each of the three clusters displays differences in the compositionof soils surrounding the castles. The catchments or areas immediatelysurrounding the castles in each of the three polities are diverse. Thisdiversity probably represents a degree of variation in the subsistenceactivities of the people in each area. In the north, castles aredisproportionately located on or adjacent to tracts of alluvium. Thesealluvial pockets occur near the coast and therefore all of the northernsites have coastal locations. In the central and southern regions inlandsites are common. Significantly, the castles in the north are often notlocated in the middle of alluvial tracts, rather they are located closeto the boundary of alluvial tracts and other types of soils. Despite thedisproportionately low number of northern castles on northern lithosols,the catchments of the castles often include considerable areas ofnorthern lithosols. This pattern is reflected in the average percentagesof the soils contained within a 500-m radius catchment surrounding the34 northern castles (FIGURE 5). A distance of 500 m was selected for theradius of the catchments as this is just under half the average distance(1.282 km) between castles. Despite there being a disproportionatenumber of castles located on alluvium with an avoidance of castles beingactually situated on northern lithosols, access to a number of differentsoils was apparently important. The mean number of different types ofsoil contained within the 500-m radius catchments of the northerncastles is 1.76, with a standard deviation of 0.61. It would appear thatit was important for the northern castles to be situated so that theirinhabitants would have had access to alluvium for taro or rice, andeither northern lithosols, podzolics, and/or forest soils for drylandagriculture. [Figure 5 ILLUSTRATION OMITTED] In the central region there is a disproportionate avoidance oflocating castles on podzolics, with an over representation of castles onforest soils. In a manner similar to the northern castles, however, thecentral castles are also situated close to the boundary of differenttypes of soil. The mean number of soils within the catchments of thecentral castles is 1.95, with a standard deviation of 0.76. The averagepercentage of the different types of soils found in the centralcatchments is shown in FIGURE 5. The catchments of the central castlesfocused on soils suitable for dryland agriculture and de-emphasizedalluvium to a greater extent than the catchments of the northerncastles. The southern castles contain the highest number of different typesof soils in their catchments (mean-2.16, s.d.=0.70). Although thesouthern castles are generally not located on the regosols of theinterior of the southern peninsula, many of the castles are locatedclose to this zone and include a large proportion of regosols in their500-m radius catchment (see FIGURE 5). There is a tendency for all of the castles, regardless of theirgeographic location, to be situated in locations that had access to morethan one soil type. Apparently situating castles in ecotones betweensoils was preferred to locating castles in the middle of one particulartype of soil. This preference, however, appears to be strongest in thesouth. Although the zones of regosols and southern lithosols are quitelarge, sites occur on or near their edges. An analysis of variance(ANOVA anovasee analysis of variance.ANOVAAnalysis of variance, see there ) of the mean number of soil types in the catchments of the threeclusters indicates that the southern castles had a significantly largernumber of different soils within their catchments than the other tworegions (F=4.498, sig.=0.012). Sub-clusters There is further patterning in the distribution of castles withineach of the three clusters. A Clark-Evans nearest neighbour coefficientof -0.204 for the 103 castles in the southern cluster suggests that thecastles are close to being distributed in a clustered manner but are, instatistical terms, randomly distributed. A plot of the log%SSE valuesfrom a K-means statistic, however, indicates that the castles in thesouthern cluster can themselves be grouped into a number of differentsub-cluster configurations. FIGURE 4 includes a graph of the log%SSEvalues for the castles in the southern cluster, inflection points on thegraph suggest that the 103 castles in the southern cluster canthemselves be grouped into 4 sub-clusters and 14 sub-clusters. The four sub-cluster configuration of the southern castles is shownin FIGURE 6. The castles in the south of the island form sub-clusters onthe small western peninsula (n=21), the southern peninsula (n=40), theeastern peninsula (n-23), and the northwest portion (n=19). The foursub-cluster solution reflects sub-groupings in the Sannan polity. Thenorthern sub-cluster includes Urasoe and Shuri castles and is the areawhere the political centre of the Chuzan Kingdom formed from the 13thcentury onwards (see FIGURE 2 for locations). The other threesub-clusters of the southern cluster correspond to powerful groupswithin the Sannan polity. The location of the capital of Sannan isdebated, with proponents divided between the sites of Shimazoe OzatoGusuku in Ozato Village, (southeast), and Shimajiri Ozato in Itoman City(southwest) (see FIGURE 2 for locations). In the Chuzan Seikan, OzatoGusuku in Ozato Village is the residence of the King of Sannan. Howeverin Ming Dynasty Ming dynasty(1368–1644) Chinese dynasty that provided an interval of native rule between eras of Mongol and Manchu dominance. The Ming, one of the most stable but autocratic of dynasties, extended Chinese influence farther than did any other native rulers of China. historical documents, Ozato Gusuku appears to refer tothe Itoman location. Takemoto & Asato (1993: 72) and Kin et al.(1988: 85) state that the Sannan capital is Shimajiri Ozato in ItomanCity. Regardless of whether the capital was in the southeast orsouthwest, it is clear that both were important centres of power formingthe nucleus of each of two of the sub-clusters. A fourth subcluster ofsites is centred around Tomigusuku, one of the larger castles in theregion. [Figure 6 ILLUSTRATION OMITTED] The 14 sub-cluster configuration of the southern cluster includes adegree of variation in the number of castles assigned to each cluster,the maximum number being 18, the minimum being 2, with a mean of 7.3 anda standard deviation of 4-6 (FIGURE 7). Five of the sub-clustersparallel groupings identified by Asato (1990: 132): sub-clusters 3(Chinen), 4, (Haebaru), 7 (Ozato), 13 (Gushichan) and 14 (Makishi).These groups are historically identified as 17th-century administrativedivisions (magiri). Four other sub-clusters show partial overlap withthe historical groups identified by Asato (1990) and five sub-clustersshow little or no isometry. [Figure 7 ILLUSTRATION OMITTED] The 55 castles assigned to the central cluster have a Clark-Evansnearest neighbour coefficient of-2.869, indicating that they themselvesare clustered. A plot of the log%SSE values from a K-means statisticshows a slight inflection point at 5 clusters (see FIGURE 4). Thecastles assigned to the 5 sub-clusters are shown in FIGURE 6. Theclustering is formed to some extent by the avoidance of podzolics and apreference for coastal locations. Four of the five sub-clusters coincidewith historically known power centers. Sub-cluster 1 is dispersed,centering on Iha. However, sub-cluster 2 is associated with a group ofcastles on the islands of Henza-Miyagi, Hamahiga, and Ikei; sub-cluster3 is associated with the Katsuren Peninsula and Tsuken Island;sub-cluster 4 includes Chatan and Nakagusuku; and sub-cluster 5 isassociated with the 15th-century Zakimi and its antecedents in theYomitan area. A Clark-Evans nearest neighbour coefficient of 0.464 for the 34castles assigned to the northern cluster indicates that they aredistributed randomly. However, the plot of the log%SSE values for thenorthern castles shows a marked inflection point at three clusters (seeFIGURE 4), and the northern castles assigned to these three clusters areshown in FIGURE 6. Again, the avoidance of lithosols and the preferencefor coastal locations are apparent. The three clusters fall generallyinto a Motobu group, dominated by Nakijin (sub-cluster 1); a group inthe Haneiji lowland area (sub-cluster 2); and a small cluster in thenorthern region around Nejana castle site (sub-cluster 3). Sites in thenorthern region of the island appear to be situated on lithosols, or onor very near alluvial pockets, which served as their agricultural base.Haneiji, for instance, is a well known center for irrigated ricecultivation, from the Gusuku Period with a dominant castle and satellitesettlements (Asato 1998: 181). Conclusion Historical evidence suggests that three polities had formed onOkinawa by the 14th century. The distribution of the fortified castlesprovides clear archaeological evidence of the three polities.Statistically the castles cluster into three groups that coincide withthe historically known political units. There is one area where thestatistical clusters and the political units do not coincide. Theinclusion of the central castles of Shuri and Urasoe in the southerngroup shows old historical links between the southern and centralclusters. In the early 14th century, Sho Shisho, founder of the FirstSho Dynasty of the Chuzan Kingdom, with the support of his sons and thelords of Sashiki in the southeast, defeated the lord of Urasoe, Bunei,and became king of Chuzan. The catchments surrounding the castles ineach cluster differ. The northern castles appear to stress access toalluvium to a greater extent than the central and southern castles. Ingeneral, however, most of the castles are located close to ecotonesbetween different types of soil. The southern castles in particular seemto be situated to take advantage of access to a number of differenttypes of soils. The castles within each of the three political unitsform sub-groupings that again often coincide with historically knownpolitical factions. This would suggest that at one time the threepolities each consisted of several smaller individual politicalfactions, which go back into the Shellmound Period (100-1100 AD) asproposed by Asato (1990: 192-3). Through time, these smaller units wereintegrated into one of the three polities, with the final integration ofthe island into a single island wide polity in the 15th century. Acknowledgements. We thank Sarina Pearson and Peter Sheppard fortheir comments on the manuscript, and Martin Bale, Warren Hill and SusanMatson for the preparation of base maps of site locations and soilzones. Research on Okinawan castle sites by Richard Pearson wassupported by grants from the Humanities & Social Sciences ResearchCouncil of Canada and the Humanities & Social Science ResearchGrants Committee of the University of British Columbia LocationsVancouverThe Vancouver campus is located at Point Grey, a twenty-minute drive from downtown Vancouver. It is near several beaches and has views of the North Shore mountains. The 7. . References ASATO, S. 1990. Kokogaku kara Mita Ryukyu Shi, Jo (Ryukyu historyas seen from archaeology 1). Naha: Okinawa Bunko bun��ko?n. & v.Variant of bunco.Noun 1. bunko - a swindle in which you cheat at gambling or persuade a person to buy worthless property . 1998. Gusuku; Kyodotai; Mura: Okinawa Rekishi Kokogaku Josetsu(Castle, co-operative group, village: an introduction to Okinawanhistorical archaeology Historical archaeology is a branch of archaeology that concerns itself with "historical" societies, i.e. those that had systems of writing. It is often distinguished from prehistoric archaeology which studies societies with no writing. ). Ginowan: Yoju Shorin. BLANKHOLM, H.P. 1990. Intrasite spatial analysis (Data West Research Agency definition: see GIS glossary.) Analytical techniques to determine the spatial distribution of a variable, the relationship between the spatial distribution of variables, and the association of the variables of an area. in theory andpractice. Aarhus: Aarhus University Press. CHINZEI, T., K. OYA & Z. KOJA. 1967. Soils and land use in theRyukyu Islands Ryukyu Islands(rē`ky), Jap. Ryukyu-retto or Nansei-shoto [southwest group], archipelago (1990 est. pop. . Shuri: University of the Ryukyus The University of the Ryukyus (琉球大学,Ryūkyū Daigaku , College ofAgriculture. FUJII, H. 1995. Chusei no Shiro to Kassen (Castles and battlefieldsof the Middle Ages). Tokyo: Asahi Shimbunsha. HANEIJI, C. 1983. Chuzan Seikan (Mirror of the ages of Chuzan Naha:Okinawa Ken Kyoiku Iinkai. (Newly edited version by Okinawa Ken KyoikuCho Bunka Ka. Original published in 1650.) KIN, S., M. TANA, I. CHINEN & S. TOMA. 1988. Gusuku RodoOkinawa no Gusuku Monogatari. Naha: Mugisha. KINTIGH, K.W. & A.J. AMMERMAN. 1982. Heuristic A method of problem solving using exploration and trial and error methods. Heuristic program design provides a framework for solving the problem in contrast with a fixed set of rules (algorithmic) that cannot vary. 1. approaches tospatial analysis in archaeology, American Antiquity 47: 31-63. OKINAWA KEN, KYOIKU IINKAI, 1983 Gusuku: Gusuku Bunpu Chosa Hokoku(1): Okinawa Honto Oyobi Shuhen Rito (Castle Sites: Report onDistribution (1): Okinawa Main Island and Surrounding Offshore Islands).Naha: Okinawa Ken Kyoiku linkai. PEARSON, R. 1992. Trade and the rise of the Okinawan State,Bulletin of the Indo Pacific Prehistory prehistory,period of human evolution before writing was invented and records kept. The term was coined by Daniel Wilson in 1851. It is followed by protohistory, the period for which we have some records but must still rely largely on archaeological evidence to Association 10: 263-81. 1997. The Chuzan kingdom, Okinawa, as a city state, in T. Charlton& D. Nichols (ed.), The archaeology of city states: cross culturalapproaches: 119-34. Washington (DC): Smithsonian Institution Smithsonian Institution,research and education center, at Washington, D.C.; founded 1846 under terms of the will of James Smithson of London, who in 1829 bequeathed his fortune to the United States to create an establishment for the "increase and diffusion of Press. 1999. Ancient Okinawa: the rise of the state. Manuscript on file,University of British Colombia. SASAKI, K. 1973. Okinawa honto ni okeru dentoteki hatasaku nokogijutsu (Traditional upland farming techniques on the Main Island ofOkinawa), Jinrui Kagaku 25: 79-107. TAKAMIYA, H. 1997, Subsistence adaptation processes in theprehistory of Okinawa. Ph.D dissertation in Anthropology, University ofCalifornia, Los Angeles UCLA comprises the College of Letters and Science (the primary undergraduate college), seven professional schools, and five professional Health Science schools. Since 2001, UCLA has enrolled over 33,000 total students, and that number is steadily rising. . TAKEMOTO, S. & S. ASATO. 1993. Okinawa: Nihon Kodai Iseki 47(Okinawa: Ancient Sites of Japan Series 47). Osaka: Hoikusha. THEGN N. LADEFOGED & RICHARD PEARSON(*) (*) Ladefoged, Department of Anthropology, University of Auckland Not to be confused with Auckland University of Technology.The University of Auckland (Māori: Te Whare Wānanga o Tāmaki Makaurau) is New Zealand's largest university. ,Auckland, New Zealand New Zealand(zē`lənd), island country (2005 est. pop. 4,035,000), 104,454 sq mi (270,534 sq km), in the S Pacific Ocean, over 1,000 mi (1,600 km) SE of Australia. The capital is Wellington; the largest city and leading port is Auckland. . t.ladefoged@auckland.ac.nz Pearson, Department ofAnthropology/Sociology, University of British Columbia, 6303 NorthwestMarine Drive, Vancouver BC, Canada V6T 1Z1. rpearson@unixg.ubc.ca Received 21 April 1999, accepted 14 July 1999, revised 6 January2000.