King Zhaoxiang of Qin
In 293 BC, East Zhou decided to ally itself with the states of Han and Wei, and sent troops to help attacking Qin. However, the combined forces of this alliance was destroyed at Yique by the young Qin general Bai Qi, with 240,000 men killed and their commander Gongsun Xi (公孫喜) captured and executed. After this loss, the East Zhou was unable to actively participate in future interstate struggles in any significant fashion.
In 256 BC, Duke Wu of West Zhou (西周武公) allied with other states to stop the Qin offensive on the Han city of Yangcheng. In retaliation, King Zhaoxiang of Qin sent general Jiu to invade West Zhou, successfully breaking into Wangcheng. The Duke Wu was taken to Xianyang to beg for mercy, conceding all his lands. Both King Nan and Duke Wu would die later that year, and the subsequent Duke of West Zhou, Duke Wen (西周文公), was exiled to Danhuju (憚狐聚). Because the Zhou royal court had fallen from power and King Nan had died without a successor, the Eastern Zhou Dynasty collapsed, ending 879 years of Zhou monarchy. The remaining East Zhou state was also conquered by Qin chancellor Lü Buwei seven years later in 249 BC during the reign of King Zhaoxiang's grandson King Zhuangxiang, after Duke Jing of East Zhou attempted to form an anti-Qin alliance with other states.
Qin dynasty
During this time, Li Si and Zhao Gao fell out, and Li Si was executed. Zhao Gao decided to force Qin Er Shi to commit suicide due to Qin Er Shi's incompetence. Upon this, Ziying, a nephew of Qin Er Shi, ascended the throne, and immediately executed Zhao Gao. Ziying, seeing that increasing unrest was growing among the people and that many local officials had declared themselves kings, attempted to cling to his throne by declaring himself one king among all the others. He was undermined by his ineptitude, however, and popular revolt broke out in 209 BC. When Chu rebels under the lieutenant Liu Bang attacked, a state in such turmoil could not hold for long. Ziying was defeated near the Wei River in 207 BC and surrendered shortly after; he was executed by the Chu leader Xiang Yu. The Qin capital was destroyed the next year, and this is considered by historians to be the end of the Qin Empire. Liu Bang then betrayed and defeated Xiang Yu, declaring himself Emperor Gaozu of the new Han dynasty on 28 February 202 BC. Despite the short duration of the Qin dynasty, it was very influential on the structure of future dynasties.