Spring and Autumn period followed by Warring States period
The Spring and Autumn period was a period in Chinese history from approximately 770 to 481 BCE (or later) which corresponds roughly to the first half of the Eastern Zhou period.  The period's name derives from the Spring and Autumn Annals, a chronicle of the state of Lu between 722 and 481 BCE, which tradition associates with Confucius (551–479 BCE). During this period, royal control over the various local polities eroded as regional lords increasingly exercised political autonomy, negotiating their own alliances, waging wars amongst themselves, up to defying the king's court in Luoyi. The gradual Partition of Jin, one of the most powerful states, is generally considered to mark the end of the Spring and Autumn period and the beginning of the Warring States period.Partition of Jin
After the great age of Jin power, the Jin rulers began to lose authority over their ministerial lineages.  A full-scale civil war between 497 and 453 BCE ended with the elimination of most noble lines; the remaining aristocratic families divided Jin into three successor states: Han, Wei, and Zhao. This is the last event recorded in the Zuozhuan.
With the absorption of most of the smaller states in the era, this partitioning left seven major states in the Zhou world: the three fragments of Jin, the three remaining great powers of Qin, Chu and Qi, and the weaker state of Yan (燕) near modern Beijing. The partition of Jin, along with the Usurpation of Qi by Tian, marks the beginning of the Warring States period.