Japan: Kofun period (about 3rd-7th century AD)
Kofun ('old mounds') refers to the distinctive practice of covering tombs with huge piles of earth. During the third and fourth centuries, clan leaders in the Yamato area of western Honshū became dominant over a federation of other Japanese kingdoms and claimed succession to the Imperial line. Centralization brought more complex social structures and the beginnings of urbanization. Contacts with the Korean peninsula and later with China itself increased rapidly. Korean migrants introduced technologies such as sword and ceramic production, and intermarried with the Japanese nobility. The end of the Kofun period marks Japan's transition to a literate culture with the introduction of the Chinese writing system, alongside the adoption of Buddhism.
Since there are no written records from the early and middle Kofun period, the tombs and grave goods are the main contributors to our appreciation of Kofun culture. The power and influence of the ruling classes is shown by the size of the mounds, from 10 metres across to the gigantic 486 metres of the moated keyhole mound of the Emperor Nintoku near Osaka (early fifth century). Grave goods include iron weapons, armour, gilt horse trappings, jewellery, bronze mirrors and pottery of increasing variety and sophistication. However, these burial practices gradually disappeared under governmental controls and the spread of Buddhism.