Especially in the Sengoku period, "daimyō" needed additional fighting men, and even if a master had perished, his "rōnin" were able to serve new lords. In contrast to the later Edo period, the bond between the lord and the samurai was loose, and some samurai who were dissatisfied with their treatment left their masters and sought new lords. Many warriors served a succession of masters, and some even became "daimyō". As an example, Tōdō Takatora served ten lords. Additionally, the division of the population into classes had not yet taken place, so it was possible to change one's occupation from warrior to merchant or farmer, or the reverse. Saitō Dōsan was one merchant who rose through the warrior ranks to become a "daimyō".