The Isshiki clan of Tango Province was originally one of the four families used by the Muromachi Shogunate for security, but it collapsed in entirety during the Sengoku (Warring States) period (Japan), with its position as Shugo (military governor) taken over by the Takeda clan of the neighboring Wakasa Province, and was then left in a situation of trying somehow or other to continue to use its influence as a ruling family of the past.
丹後の一色氏は元々室町幕府の四職の一家であったが、戦国時代(日本)には没落の一途をたどり、丹後の守護職も隣国の若狭武田家に奪われる有様で、かつての守護家の権威を利用しどうにか実効支配を続ける状態であった。