The branch of the Ishikawa family which thrived as fudai daimyo (a daimyo in hereditary vassal to the Tokugawa family) in the Edo period had been derived from the lineage of Ienari ISHIKAWA, who was an uncle of Kazumasa.
江戸時代に譜代大名として隆盛した石川氏の系統は数正の叔父の石川家成の系統である。