じょうばんぎょりゅうであれば
常磐御柳であれば
jōbangyoryūdeareba

Noun
Da Copula

The "-eba" conditional form ("if/when…") of ときわぎょりゅう

1. If it were Joban no Yanagi…; If Joban no Yanagi existed…

Ba Conditional
Usually Written in Kana