Emperor Kanmu moves the capital to Heian-kyō (Kyoto)

Kanmu, emperor from 781, wanted to put distance between his court and the increasingly politicized Buddhist clergy of Nara, and in 784 he moved to Nagaoka-kyō, about 40 km to the north, where three rivers meet and supplies could come by boat; the Shoku Nihongi records that he took up residence in the new palace on 27 December 784. The new city brought misfortune. In 785 Fujiwara no Tanetsugu, one of those in charge of building it, was shot dead; Crown Prince Sawara, who had opposed the move, was imprisoned and exiled and died on the way. When drought, famine and epidemics followed, a diviner declared in 792 that the disasters were the work of Sawara’s vengeful spirit, and soon afterwards heavy rains twice flooded Nagaoka-kyō.

Wake no Kiyomaro, the official in charge of flood control, proposed another move. In the first lunar month of 793 Fujiwara no Oguromaro and Ki no Kosami were sent to survey Uda village in the Kadono district, and building began soon after. On 18 November 794 Kanmu entered the new capital, and on 4 December an edict declared that ‘this land, girdled by mountains and rivers, forms a citadel by nature’: the province, until then written as Yamashiro ‘behind the mountains’, was renamed ‘mountain citadel’, and the city was called Heian-kyō, because, the edict said, the people who had come to build it and those who sang its praises called it so with one voice. The ‘praises’ are usually linked with the refrain of a dance-song performed at a palace banquet in 795: ‘Joy of the new capital, Heian, land of joy, spring for ten thousand years’.

The city, about 4.5 km from east to west and 5.2 km from north to south, followed the plan of Chang’an: the Suzaku avenue divided it into a left and a right capital, and only two state temples, Tō-ji and Sai-ji, were allowed within it. Heian-kyō remained the seat of the emperors — and, by one reckoning, the capital of Japan — until the court moved to Tokyo in 1869, and the Heian period is named after it.