Regardless of the origins of the Soga clan, its deep ties with migrant clans is without-doubt, immigrants to ancient Japan; and it is thought that the rise of the Soga clan was aided by the relatively advanced technologies introduced to Japan by Shinabe (technicians in offices) who were toraijin (settlers), who became subjects to royal authority as indentured professionals.
蘇我氏自身の出自はともかく、渡来系の氏族と深い関係にあったのは確かなようで、王権の職業奴属民としての役割を担っていた渡来人の品部の集団などが持つ当時の先進技術が蘇我氏の台頭の一助になったと考えられている。