Rubuta ci gaba don wannan sakin layi - Yankin Kagamiishi na yau ya kasance wani ɓangare na tsohuwar lardin Mutsu kuma ya kasance wani ɓangare na mallakar Shirakawa Domain a lokacin Edo. Bayan Maido da Meiji, an shirya shi a matsayin wani ɓangare na Gundumar Iwase a yankin Nakadōri na Lardin Iwashiro. An kafa ƙauyen Kagamiishi a ranar 1 ga Afrilu, 1889 tare da ƙirƙirar tsarin birni na zamani. An daukaka matsayin gari a ranar 1 ga Agusta, 1962. A lokacin girgizar kasa ta 2011 Tohoku
, sama da gine-gine 1000 sun lalace ko lalacewa, daidai da kusan kashi 23 cikin dari na garin,