Abe no Yoritoki (安倍頼時) (died 28 August 1057) was the head of the Abe clan of Emishi who were allowed to rule the six Emishi districts (Iwate, Hienuki, Shiwa, Isawa, Esashi and Waga) in the Kitakami Basin [ja] from Morioka to Hiraizumi in what is now Iwate Prefecture.
The clan emerged from the Appi River basin in what is now Hachimantai City, Iwate Prefecture, early in the 9th century.
By monopolizing the gold, iron and horse trade in northern Honshū the family became enormously wealthy.
The 9th and 10th centuries saw a weakening of central power as a new land management system of tax-immune estates, or shoen, took hold.
[1] Yoritoki's sons continued fighting for a time but were finally overwhelmed by combined Minamoto and Kiyowara armies in 1062.