Kings of the Han dynasty
The kings from other dynasties (, "yìxìng wáng") were mostly remnants of the rebellion against the Qin dynasty. Following the Dazexiang Uprising, many noblemen rose in rebellion. Heirs, pretenders, and warlords called themselves "kings" and claimed sovereignty as continuations of the six states previously suppressed by Qin. Among these, Chu was the most powerful. However, its rightful ruler Huai II was assassinated on the orders of the warlord Xiang Yu and the 18 Kingdoms Xiang had formed rose in rebellion against him. Liu Bang, king of Han, ultimately defeated Chu and established the new Han dynasty. The kings who had sided with him were then permitted to maintain their titles and lands. A few other kingdoms were also formed by Liu Bang for generals and favorites.
Zhang Liang (Western Han)
In 202 BC, after his victory over Xiang Yu, Liu Bang ascended the throne and became historically known as "Emperor Gaozu of Han". Following the establishment of the Han dynasty, Zhang Liang remained as a key advisor to Gaozu even though he did not receive any formal appointment as a government minister. Together with Lou Jing, Zhang Liang later suggested for Gaozu to build his capital in Chang'an instead of Luoyang, as Chang'an was in a more strategic position than Luoyang (fertile land and surrounded by natural defences such as mountain passes). Once, Gaozu noticed that some of his subjects were having a secret discussion and he asked for Zhang Liang's opinion. Zhang Liang told Gaozu that they were plotting a rebellion and Gaozu was shocked. Zhang Liang proceeded to ask Gaozu whom of all his subjects he hated the most. Gaozu mentioned Yong Chi, who had rebelled against him before but surrendered later. Zhang Liang then suggested to Gaozu to grant Yong Chi a noble title, because if the others saw that Gaozu was able to forgive Yong Chi, they would be at ease and would not think of rebelling.