Warring States period
Qi and Wei became kingdoms (344 BC)

The title of king (wang, 王) was held by figurehead rulers of the Zhou dynasty, while the rulers of most states held the title of duke (gong, 公) or marquess (hou, 侯). A major exception was Chu, whose rulers were called kings since King Wu of Chu started using the title c. 703 BC.

In 344 BC the rulers of Qi and Wei mutually recognized each other as kings: King Wei of Qi and King Hui of Wei, in effect declaring their independence from the Zhou court. This marked a major turning point: unlike those in the Spring and Autumn period, the new generation of rulers ascending the thrones in the Warring States period would not entertain even the pretence of being vassals of the Zhou dynasty, instead proclaiming themselves fully independent kingdoms.
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