Chinese 曹: there are two main branches of the Cao line. One branch comes from Cao An, a great-grandson of the emperor Zhuan Xu (26th century BC). A descendant named Cao Xie was granted the state of Zhu when the Zhou dynasty came to power in 1122 BC. When Zhu was conquered by the state of Chu, many of the Zhu aristocracy adopted a modified form of the character Zhu as their surname (see Chu), but others kept the name Cao. The origin of the other branch also involves the granting of a state at the beginning of the Zhou dynasty: in 1122 BC Zhen Duo, a son of Wen Wang, was granted the state of Cao, a name subsequently adopted by his descendants. Other Romanized forms of this name include Tso, Cho, Tsao and Chou.