In 1884 a shell mound site in the Yayoi district of Tokyo yielded pottery finds that were initially thought to be variants of Jōmon types but were later linked to similar discoveries in Kyushu and Honshu. Scholars gradually concluded that the pottery exhibited some continental influences but was the product of a distinct culture, which has been given the name Yayoi.

Both archaeological and written evidence point to increasing interaction between the mainland and the various polities on the Japanese archipelago at this time. Indeed, the chronology of the Yayoi period (c. 3rd century bce–c. 250 ce) roughly corresponds with the florescence of the aggressively internationalized Chinese Han dynasty (206 bce–220 ce). Chinese emissarial records from that period include informative observations about customs and the sociopolitical structure of the Japanese population. The Chinese noted that there were more than 100 distinct “kingdoms” in Japan and that they were economically interdependent but also contentious. Other records suggest that the inhabitants of the archipelago traveled to the Korean peninsula in search of iron.

The Yayoi culture thus marked a period of rapid differentiation from the preceding Jōmon culture. Jōmon, a hunting-and-gathering culture with possibly nascent forms of agriculture, experienced changes and transitions primarily in reaction to climatic and other natural stimulants. Yayoi, however, was greatly influenced by knowledge and techniques imported from China and Korea. The impact of continental cultures is decidedly clear in western Japan from about 400 bce, when primitive wet-rice cultivation techniques were introduced. Attendant to the emerging culture based on sedentary agriculture was the introduction of a significant architectural form, the raised thatched-roof granary.

The Tumulus period

About 250 ce there appeared new and distinctive funerary customs whose most characteristic feature was chambered mound tombs. These tumuli, or kofun (“old mounds”), witnessed significant variations over the following 450 years but were consistently present throughout the period to which they gave their name. Some authorities have suggested that the development of these tombs was a natural evolution from a Yayoi-period custom of burial on high ground overlooking crop-producing fields. While partially convincing, this theory alone does not account for the sudden florescence of mound tombs, nor does it address the fact that some aspects of the tombs are clearly adaptations of a form preexisting on the Korean peninsula. Indeed, implements and artifacts discovered within these tombs suggest a strong link to peninsular culture.

Changes in tomb structure, as well as the quantity, quality, and type of grave goods discovered, offer considerable insight into the evolution of Japan’s sociopolitical development from a group of interdependent agricultural communities to the unified state of the early 8th century. Of course, the material culture of the Tumulus period extended far beyond the production of funerary art. For example, it is in this time that an essential form of Japanese expression, the Chinese writing system, made its appearance on the archipelago—a fact known from such evidence as inscribed metal implements. This system had a profound and comparatively quick influence not only on written language but also on the development of painting in Japan. Nevertheless, tombs are the repositories of the period’s greatest visual achievements and are excellent indicators of more general cultural patterns at work. And, in that wider context, three distinct shifts in tomb style can be discerned that define the chronology of the period: Early Kofun of the 4th century, Middle Kofun covering the 5th and early 6th centuries, and Late Kofun, which lasted until the beginning of the 8th century and during which tomb burials were gradually replaced by Buddhist cremation ceremonies. The Late Kofun roughly coincides with the periods known to art historians as the Asuka (mid-6th century–645) and the Hakuhō (645–710).

Tombs of the Early Kofun period made use of and customized existing and compatible topography. When viewed from above, the tomb silhouette was either a rough circle or, more characteristically, an upper circle combined with a lower triangular form, suggesting the shape of an old-fashioned keyhole. The tombs contained a space for a wooden coffin and grave goods. This area was accessed through a vertical shaft near the top of the mound and was sealed off after burial was completed. The deceased were buried with materials that were either actual or symbolic indicators of social status. Adorning the summit of the mound and at points on the circumference midway, at the base, and at the entrance to the tomb were variously articulated clay cylinder forms known as haniwa (“clay circle”). These were an unglazed, low-fired, reddish, porous earthenware made of the same material as a type of daily-use pottery called haji ware. These clay creations were shaped from coils or slabs and took the form of human figures, animals, and houses.

After the 4th century, tomb builders abandoned naturally sympathetic topography and located mounds in clusters on flat land. There are differences in mound size, even within the clusters, suggesting levels of social status. The scale of these tombs, together with construction techniques, changed considerably. The tomb generally assumed to be that of the late 4th-century emperor Nintoku, located near the present-day city of Ōsaka, measures nearly 1,600 feet (500 metres) in length and covers 80 acres (32 hectares). It is alternately surrounded by three moats and two greenbelts. Approximately 20,000 haniwa were thought to have been placed on the surface of this huge burial mound.

In the later part of the 5th century, the vertical shaft used to access the early pit tomb was replaced by the Korean-style horizontal corridor leading to a tomb chamber. This made multiple use of the tomb easier, and the notion of a family tomb came into existence.

Late Kofun tombs are characterized by schemes of wall decoration within the burial chambers. Two especially important tombs have been excavated in the area just to the south of present-day Nara. The Takamatsu tomb (discovered 1972) and the Fujinoki tomb (1985) suggest high levels of artistic achievement and a sophisticated assimilation of continental culture. The Takamatsu tomb is noted for its wall paintings containing a design scheme representing a total Chinese cosmology. Included are especially fine female figure paintings. At Fujinoki exquisite and elaborate metalwork, including openwork gold crowns, a gilt bronze saddle bow, and gilt bronze shoes, was discovered. Design motifs show evidence of Chinese, Central Asian, and Indian sources.