In Mikawa Province, he extended his power by inviting the Okochi clan, the grandchildren of MINAMOTO no Yorimasa, as his generals before the Okochi clan was adopted by the Nagasawamatsudaira family, and he let Osauji KIRA, his eldest child born out of wedlock, settle at the Kira-sou in Hazu District (presently located between Hazu District and Nishio City, Aichi Prefecture) and formed the Kira clan, a branch family of the Ashikaga clan (later, the Imagawa clan became a branch family of the Kira clan).
三河国では源頼政の孫大河内氏長沢松平家に養子になる前などを家臣に入れ勢力を拡大し、庶長子の吉良長氏を幡豆郡吉良荘（現在の愛知県幡豆郡から西尾市）に住ませて足利氏の分家吉良氏（後に今川氏が分家）を誕生させた。