Etymology and distribution of 出後.

Izugo 【出後】^{レベル2
About 10}  The Japanese surnames etymology dictionary.

Hokkaidou Sapporo - shi Kita - ku. There is 一宮 surname. Saitama-ken Gyouda-shi Honmaru was in the Edo period as a shrine clan of the Clan office. 一宮 Ichimiya reference.