Etymology and distribution of 眞上.

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

Nagano-ken Nagano-shi . There was a name of Genji in the warrior of the Heian period. 源 Minamoto reference. Nagano-ken Nagano-shi Wako Uchijima is based. In the same place tells that he was a vassal of Takeda Shingen, a warrior of warring States era with Yamanashi-ken as the base.