Fujiwara no Umakai
- Born: 694
- Died: 737
- Titles: Governor of Hitachi province (c. 719-723)
- Distinction: third son of Fujiwara no Fuhito
- Japanese: 藤原宇合 (Fujiwara no Umakai)
In 719, Fujiwara no Umakai became governor of Hitachi province, having just returned to Japan from China where he was vice-envoy Kentoshi. In his new post, he was also in charge of inspecting the leadership of Kazusa, Awa, and Shimotsu Fusa provinces.
By 724 he headed the Ministry of Ceremonies, and held Upper Senior 4th rank. In the same year he was appointed General-in-chief to suppress the Emishi in northeastern Japan. For his military service he was promoted again, this time to the Junior 3rd rank.
An accomplished poet, the Man'yoshu contains six of his works, with others in the collection Yearnings for the Ancient Chinese Style.
Along with three of his brothers, Umakai died in a nationwide outbreak of smallpox that killed numerous aristocrats, and it is suggested in the Cambridge History of Japan, "approximately one-third of the entire population perished during those two years." At his death he held Senior 3rd rank and was an Adviser of the State Council, Minister of Ceremonies, and concurrent Director of the Dazaifu.
- Mark C. Funke, "Monumenta Nipponica", "Hitachi no Kuni Fudoki"
- Wang, Zhenping. Ambassadors from the Islands of Immortals: China-Japan Relations in the Han-Tang Period, Association for Asian Studies and University of Hawai'i Press, HI, 2005.
- Delmer M. Brown, John Whitney Hall, et al (eds.), The Cambridge History of Japan, vol 1 (1988), 250-251.