- Born: 626
- Died: 671
- Reign: 668-671
- Other Names: 葛城 (Kazuraki), 中大兄 (Naka no Ôe), 天命開別 (Ame Mikoto Hirakasu Wake)
- Japanese: 天智天皇 (Tenji Tennô)
Emperor Tenji, known throughout most of his career as Prince Naka no Ôe, was one of the major political figures of the Asuka Period.
He was the second prince born to Emperor Jomei 舒明天皇.
In 645 with the help of Nakatomi no Kamatari 中臣鎌足 (later Fujiwara no Kamatari) he destroyed the Soga clan 蘇我氏. The same year he carried out the very significant Taika Reforms. After the death in 661 of his mother, the ruling emperor Empress Seimei, he took the position of regent and in 667 moved the capital to Ôtsu no Miya in Ômi province, but did not actually ascend the throne till 668. He created the Kôgo-year Register of Families, the first such nation-wide register, in 670, and promulgated the Ômi Law Code.
Morris in The Nobility of Failure has a chapter discussing him as the "successful villain" in contrast to his cousin Arima no Miko 有間皇子, son of Emperor Kôtoku, whom he executed on a rather doubtful charge of plotting a revolt.
For the Taika Reforms see Sources of Japanese Tradition