However, the family of Norimitsu Isshiki, the second child of Noriuji, rendered distinguished service; therefore, the family power was regained to become shugo (guard feudal lord) of Mikawa-no-kuni, Wakasa-no-kuni and Tango-no-kuni, and also held the reins of power as one of the Shishiki families, in what was the most flourishing time for the Isshiki clan.
しかし、範氏の次子の一色範光の一族が功績をたて家勢を回復し、三河国・若狭国・丹後国の守護大名となると同時に、四職家の一つとして権勢を奮い、一色氏は最盛期を迎えた。