Qin dynasty
Note: King Zhaoxiang of Qin (秦昭襄王) had already been ruling Qin for 51 years when Qin annihilated the Zhou dynasty; however the other six warring states were still independent regimes. Some Chinese historiographers thus used the next year (the 52nd year of King Zhaoxiang of Qin) as the official succession from the Zhou dynasty.
Chu–Han Contention
In 221 BC, the Qin state unified China by conquering the other six major states and established the Qin dynasty. However, the oppressive and extremely unpopular dynasty lasted only 14 years. In 209 BC, Chen Sheng and Wu Guang started the Dazexiang Uprising to overthrow the Qin dynasty.