Japanese History Digest

Kofun period

The Kofun period, following the Yayoi period, saw the active construction of various types of kofun tombs across the Japanese archipelago, including keyhole-shaped tombs. It is believed to have lasted from roughly the mid-3rd century to the end of the 6th century. During this period, huge keyhole-shaped tombs appeared in the Yamato region, centered around Nara Prefecture, and spread throughout the country. The size and shape of a kofun tomb indicate the status and power of its entombed occupant, with examples such as the Daisen Tomb (the tomb of Emperor Nintoku) and the Hashihaka Tomb being particularly notable.

One of the defining features of the Kofun period was the establishment of the so-called "Yamato government" (a term later used in research). The Yamato government was formed as a coalition of powerful clans, and its rulers were called "okimi" (great kings). The government established the clan and surname system and the bemin system, systematically controlling clans and local leaders. This system established clans, which represented bloodline groups, and surnames, which indicated the status and function granted to each clan, strengthening central and local control.

Many immigrants from the Korean Peninsula also arrived in Japan during this period, bringing with them new technologies and culture, including iron tools, horses, metalworking techniques, and steamers. The spread of iron tools improved agricultural productivity, and the development of weapons and farm tools promoted social change. Furthermore, a variety of grave goods, including bronze mirrors, weapons, and ornaments, have been discovered in kofun tombs, suggesting the international exchange and increasingly complex social structure of the time.

It is believed that during the early Kofun period, Wa (Japan) advanced into the Korean Peninsula in search of iron resources and advanced technology. Records on the King Gwanggaeto Stele suggest there may have been military tensions between Wa and Goguryeo. Furthermore, from the late 4th century to the early 5th century, the power dynamics surrounding Baekje and Silla became more complex.

The Iwai Rebellion occurred in Tsukushi Province (present-day Fukuoka Prefecture) in the first half of the 6th century. In 527, Tsukushi no Kimi Iwai rebelled in opposition to the Yamato government's military expedition to the Korean Peninsula. The rebellion was suppressed the following year by Yamato imperial forces. This incident demonstrates the continued strength of local clans and the expansion of the Yamato government's control.

Buddhism was also introduced to Japan during the late Kofun period. The Jōgū Shōtoku Hōō Tei-setsu records it as 538, while the Nihon Shoki records it as 552, but academic opinion is divided. It is believed that King Seong of Baekje presented Emperor Kinmei with a Buddhist statue and sutras, sparking a debate between the Soga and Mononobe clans over the acceptance of Buddhism. Ultimately, Soga no Umako emerged victorious, and Buddhism became firmly established in Japanese society. Furthermore, towards the end of the period, conflicts within the government intensified, culminating in the assassination of Emperor Sushun by Soga no Umako in 592. This was the only confirmed assassination of an emperor in Japanese history, and was an event symbolizing the expansion of the Soga clan's power and the political turmoil.

Towards the latter part of the Kofun period, the construction of large kofun tombs decreased, and instead, smaller cluster tombs were built in various places. This change is thought to indicate the spread of unique expressions of authority by local clans. Eventually, in the 7th century, with the spread of Buddhist culture and preparations for the introduction of the Ritsuryo system, kofun construction came to an end, and the era transitioned into the Asuka period.

Timeline of the Kofun period

313 AD	Goguryeo annexed Lelang Commandery.
391 AD	Wa (Japan) engaged in battles with Goguryeo.
478 AD	The King of Wa, Bu, submitted a memorial to the Emperor Jun.
512 AD	Ohtomo no Kanamura ceded four counties of Kara to Baekje.
527 AD	The Iwai Rebellion occurred in Tsukushi Province.
538 AD or 552 AD	Buddhism was introduced to Japan and there are two theories regarding the year it was introduced.
562 AD	Kara ceased to exist.
587 AD	Mononobe clan ceased to exist.
589 AD	Sui Dynasty unified the Northern and Southern Dynasties.
592 AD	Emperor Sushun was assassinated.

Facilities where you can learn about the Kofun period

The Tomb of Emperor Nintoku
https://www.sakai-tcb.or.jp/spot/detail/126

Inariyama Kofun
http://www.sakitama-muse.spec.ed.jp/?page_id=158

Isonokami Jingu
https://www.isonokami.jp/

Japanese History Digest