Why did Liu Bang leave Chu?

Liu Bang was born in Xuzhou. During the Warring States Period, Xu was destroyed by Chu.

The time when Qin ruled Xuzhou was not as long as that of Chu. Coupled with the anti-Qin at that time, of course, the slogan "Although there are three Chu, Qin will be destroyed" was played, calling itself Chu.

At that time, Liu Xiangyu became sworn brothers and was awarded the title of * * * by Yidi Chu Huaiwang.

Later, because Liu Bang was sent by Xiang Yu to Hanzhong (another territory of Chu), he called himself Hanwang.