Samurai were at the heart of the early modern political order, and their vision of human relations dominated the political structure and the economy. They were warriors whose success depended on faithful service to the right lord. Yamauchi Katsutoyo received the domain of Tosa in 1600 for his service to Ieyasu at the battle of Sekigahara. This realm made Katsutoyo wealthy, yet it was a domain and a wealth that he had to be ready at any moment to devote to his overlord's command. Katsutoyo demanded no less from his retainers, whom he enfeoffed, and not much less from leading merchants and peasants, who were required to help Katsutoyo and his descendants serve.