The Ozuki clan, which had served kanmu (the term 'kanmu' was the collective name of the offices of the sadaishi [senior recorder of the left] and the udaishi [senior recorder of the right] which had been inherited exclusively by the Ozuki family since the Heian period and the Mibu family since the Sengoku [Warring State] period) for generations, was divided into the Omiya Kanmu family which was founded by OZUKI no Naganari and the Mibu Kanmu family which was founded by his younger brother OZUKI no Takamoto in the early Kamakura period, and these two families had contended for the position of kanmu since then.
代々官務を務めた小槻氏は、鎌倉時代初期に小槻永業を祖とする大宮官務家と弟の小槻隆職を祖とする壬生官務家に分裂して官務の地位を争った。