Originally, shinkai were granted to shrines and were not inherited by a shrine which the enshrined deity was moved to, but with the fall of the Ritsuryo system, these shrines also carried the shinkai of their original shrines.
本来神階は神社に対して授けられるもので分祀先には引き継がれないが、律令制の崩解とともに分祀先でも元の神階を名乗るようになった。