Ezozata

…This has been the prevailing view since the Edo period historical text Buke Myomokusho, but looking at existing historical materials, the name Ezo Kanrei was first seen in the Suwa Daimyojin Ekotoba, created in 1356 (Shohei 11, Enbun 1), and appears to have been a name that reflected the names of offices in the early Muromachi Shogunate, such as Kanto Kanrei and Oshu Kanrei. In Kamakura period historical materials, it is written as Ezo Sata or Toi Seibai. In the law text Sata Mirensho, created at the end of the Kamakura period, Toi Seibai is positioned as an important governmental affair of the Shogunate. …

*Some of the terminology explanations that refer to "Ezo Sata" are listed below.

Source | Heibonsha World Encyclopedia 2nd Edition | Information

…江戸期作成の故実書《武家名目抄》以来の通説であるが，現存史料でみると，蝦夷管領の名称は，1356年(正平11∥延文1)作成の《諏訪大明神絵詞》を初見史料とし，関東管領，奥州管領など室町幕府初期の職制名称を反映した呼称であったとみられる。鎌倉期史料では，蝦夷沙汰または東夷成敗と表記。鎌倉末期作成の法律書《沙汰未練書》では，東夷成敗を幕府の重大政務として位置づけている。…

※「蝦夷沙汰」について言及している用語解説の一部を掲載しています。

出典｜株式会社平凡社世界大百科事典 第２版について | 情報