 Toyotomi retainer Yamauchi Kazutoyo was assigned Kakegawa, and considerably improved on the structure of the castle and its moat system.After the Battle of Sekigahara, Tokugawa Ieyasu regained control over the Tōkai region, and Yamauchi Kazutoyo surrendered Kakegawa in exchange for Tosa Province in Shikoku.In February 1601, Hisamatsu Sadakatsu, Ieyasu's half-brother, was made "daimyō" of the new Kakegawa Domain with revenues of 10,000 "koku".