In the 12th century, two military clans, the Minamoto and the Taira, were very powerful. They controlled Japan. They fought wars against each other. In 1192, Minamoto no Yoritomo became the first shogun. He became the ruler of all of Japan. He started a new government in Kamakura. This “Kamakura” government was from 1185-1333. It made the samurai the ruling class of Japanese society.