The clans soon began to fight among themselves. During the time of Duke Ding of Jin (511-475), the Fan and Zhonghang clans were eliminated by Xiangzi of Zhi. By about 450BC, the Zhi were dominant and began demanding territory from the other clans. When Zhao resisted, Zhi attacked Zhao and brought along Han and Wei as allies. After a long siege at Taiyuan, Han and Wei switched sides and the three weaker clans annihilated the Zhi. They then divided the Zhi lands, as well as most of the rest of Jin, among themselves. When Duke You of Jin (433-416) came to the throne, the three clans had taken over much of the remaining Jin lands, leaving the dukes only the area around Jiang and Quwo. From then on, the three clans were known as the "Three Jins" (三晉).