Some aspects of the history and culture of Kaya, a confederation of city-states established about two millenia ago near the mouth of the Naktong River, have been revealed through a series of excavations made since the 1970s. However, as these archaeological studies were either incomplete or concentrated on limited areas, more extensive excavations and research have been called for. In this respect the recent excavation of a cemetery of pit burials in Yangdong-ri is significant because it has provided valuable information about the history and culture of Kuyaguk and Pon-Kaya, two Kaya polities that once stood along the lower reaches of the Naktong. The cemetery is located about 4 kilometers to the southwest of downtown Kimhae on a rolling hill (90 meters above sea level) behind Kagok village and beside the Namhae Expressway. At first, the site, 24 acres of land in Yangdong-ri, Chuch’on-myon, Kimhae, Kyongsangnam-do, did not appear to be of any historic value except for a scattering of pottery shards from damaged tombs. Nevertheless, an excavation was undertaken because Kimhae County had designated part of the area as the site for a new rice mill. Once the surface layer was removed, the excavation crew found a cluster of relics. As valuable artifacts kept coming to light, the first excavation continued for 22 months and, because of the importance of the findings two more excavations have been undertaken.
The excavations, under the supervision of experts from Dongeui University’s museum from November 1990 through February 1996, covered an are-d of about 13,200 square meters (32 acres). A total of 562 burial sites including wood coffin tombs, outer coffin tombs, vertical stone chamber tombs and pr coffins were uncovered. From them, a total of 4,952 artifacts including 1.925 pieces of pottery, 2,889 metal 31objects, 45 bronze objects, 69 ornaments and 24 miscellaneous objects were recovered. The artifacts are believed to date from the late second century BC to the fifth century A.D., while the burials appear to have been made from the first century through the fifth century, judging from the various burial styles and changes.
Studies revealed that the tombs in Yangdong-ri were of six different styles representing almost all of the known Kaya tomb styles. The findings helped clarify the development of the Kaya burial system, from wood coffin tombs to outer coffin tombs to venial I stone chamber tombs. Judging from the wood coffin tombs, Kaya’s history is believed to date back to as early as the first century B.C., instead of the early first century A.D. as most historians have postulated. The discovery of large outer coffin tombs, 5 meters or larger, which provides a key to understanding the development of Kaya, pushes their origin back to the late second century A.D. rather than the end of the third century A.D. as was previously thought The decisive due was Outer Coffin Tomb No. 162, which is the oldest large-scale outer coffin tomb of Kaya ever found. It contained ‘”s many as 10 bronze mirrors, the most ever found in a Korean tomb. In addition to this find, a number of large tombs believed to have been made for chieftains in the late second century A.D. and the third century A.D. were uncovered, making it possible to discuss when such tombs were made and for whom. Depending on the outcome of such discussions, these tombs could be classified as “Kaya Tombs of the Emergent Stage (or Early Age).” In six tombs, the interior of the burial chamber was scorched, a special burial style believed to have been influenced by a style practiced in the northern pans of the peninsula.
The artifacts from the Yangdong-ri tombs provide a comprehensive view of the changes and development of Kaya’s culture by period and information about many missing links in the study of Kaya history. The information gleaned from the pottery, iron, bronze and ornamental pieces and other materials suggests that the current history and chronology of Kaya should be revised. It also indicates that Kaya was a comparatively advanced society that had contacts with other kingdoms and cultures of the period.
Among the major artifacts excavated are such iron craft as various weapons, helmets, armor, horse trappings and farming tools, which indicate the dynamism of Kaya society at that time. A sword with a round pommel and a spear with an iron grip from Outer Coffin Tomb No. 235 (dating back to the third century A.D.) and iron objects of deviant shapes with whorling patterns and swords from Outer Coffin Tomb No. 212 (the late second century A.D.) and Outer Coffin Tomb No. 313 (the third century A.D.) are the first, the oldest or the largest of their kind excavated in Korea. The whorling patterns are believed to have been a symbol of Kaya, possibly belonging to a king or a shaman officiant of rites. The bronze artifacts include objects that represent the last stage of the native bronze tradition as well as unusual ritual vessels, daily utensils and ornaments probably imported from other cultures. By further studying the functions, sources and dates of the objects, archaeologists can now find clues, about Kaya’s contact and trade with other countries as well as its social structure and international standing. Of special note are the bronze mirror and bronze dagger retrieved from Tomb No. 427. The bronze mirror is of what is called “imitation mirror” or “Japanese mirror” and the bronze dagger is a deviant Korean dagger. Both were the first discoveries of such objects in Korea. Viewed from the perspective of the development of Korean bronze ritual vessels, they illustrate the changes made in the early Kaya period to the ritual bronze vessels of Korea represented by bronze mirrors with fine, linear designs and knobs on the back and slender (Korean type) daggers. These discoveries suggest that Kaya was the first society to manufacture and trade bronze ritual vessels on a large scale. Accordingly, the imitation (or Japanese) mirrors and deviant slender (Korean type) daggers that continue to he excavated both in Korea and Japan should be reclassified as Kaya-, Kimhae- or Yangdong-ri-type bronze mirrors and bronze daggers.
Most of the ornaments are of various shapes and made of beads. The most notable of them are the chest and neck ornaments from Outer Coffin Tombs No. 270 and 322, which are rated as the best of all Kaya ornaments discovered in size and exquisiteness. The Yandong-ri tumuli are important because they provide substantive information about the development of Kaya is culture by period and enable archaeologists to develop advanced theories about the nature and course of Kaya’s national and social development. They suggest that Kuyaguk and Pon-Kaya, centered around Kimhae on the downstream reaches of the Naktong River, were Korea’s first maritime states involved in trading activities. Kaya’s maritime prosperity, alluded to in an entry on the iron trade in the Tung-j chuan (Account of the Eastern Barbarians) in the Chinese source Sankuo-chi (History of the Three Kingdoms), is now supported by the abundance of iron artifacts excavated from the Yangdong-ri site. The period from the late second century through the fourth century, in particular, was the acme of “Kaya iron.” It was also during this period that maritime trading thrived.
Assuming that Kaya’s mastery in the production of iron, the most important natural resource at the time, was the major factor in its becoming a great maritime kingdom, the devaluation of Kaya iron and the decline in demand for its products must have contributed greatly to Kaya’s downfall. Kaya began to show signs of waning at the turn of the fifth century A.D. and the pressure of the newly emerging Shilla and Paekche kingdoms hastened its demise, which came in 562.