Etymology and distribution of 大氏.

Oouji 【大氏】^{レベル2
About 40}  The Japanese surnames etymology dictionary.

Gunma-ken , Saitama-ken , Tochigi-ken . A variant of 小柴 . Gunma-ken Fujioka-shi Mr. Koshiba who had a marital relationship with Heike in Uchinohino and Shimano, declares "Koshiba" to disguise himself as a secret evasion in the Kamakura period after Heike's destruction. 小柴 Koshiba reference. 平 Taira reference. Gunma-ken Isesaki-shi Bokoko Konki is a place name with a record since the Muromachi Period. The place name is estimated from the person's name.