Wikipedia
The was a cadet branch of the Fujiwara clan founded by Fujiwara no Umakai, i.e., one of the four great houses of the Fujiwara, founded by the so-called , who were sons of Fujiwara no Fuhito.
The name derives from the fact that the founder Umakai held the office of , or the head of the . Thus Shikike may be translated the "Ceremonials House."
The other branches were the Nanke (the eldest brother Muchimaro's line), Hokke ( Fusasaki's line), and the Kyōke ( Fujiwara no Maro's line).
Umakai's son mounted a rebellion named after his name in 740, which ended with suppression and his death, spelling ill-fortune for the Shikike. The Nanke then gained hegemony again (back from the non-Fujiwara Tachibana no Moroe) until Nakamaro mounted his own uprising.
Shikike came into ascendancy with Fujiwara no Momokawa. The notorious who enticed and held sway over Emperor Heizei is also of the Shikike clan.