24 events the sources record for this year, grouped by region.
What happened
China (17)
Xiang Yu moved west, massacred Xianyang, killed the surrendered Ziying and burned the Qin palaces; the people of Qin were deeply disappointed. (Book of Han (Hanshu), Imperial Annals 漢書卷001 漢高祖元年(鴻門 이후, 월 불명))
Xiang Yu proclaimed himself Hegemon-King of Western Chu and made Pengcheng his capital; breaking his pledge, he made the Duke of Pei King of Han, with the forty-one counties of Ba, Shu and Hanzhong and the capital at Nanzheng. (Book of Han (Hanshu), Imperial Annals 漢書卷001 漢高祖元年二月)
When the King of Han reached Nanzheng, his soldiers, wanting to return east, deserted; Xiao He recommended Han Xin, and on an altar he was appointed Grand General. (Book of Han (Hanshu), Imperial Annals 漢書卷001 漢高祖元年四月~)
The King of Han came out by the old road and attacked Yong; at Chencang he defeated the King of Yong, Zhang Han, beat him again at Haozhi, and drove him back to Feiqiu. (Book of Han (Hanshu), Imperial Annals 漢書卷001 漢高祖元年五月)
Xiang Yu broke through Hangu Pass and reached west of Xi, meaning to attack Duke Pei; but through Xiang Bo's mediation a banquet was held at Hongmen (the Hongmen Banquet). (Records of the Grand Historian (Shiji), Annals 史記卷007 項羽本紀)
Xiang Yu went west and slaughtered Xianyang, killed the King of Qin Ziying and burned the palaces; the fire did not go out for three months. (Records of the Grand Historian (Shiji), Annals 史記卷007 項羽本紀)
Xiang Yu divided the world, set up feudal lords, made himself Xichu Hegemon-King, governed nine commanderies and made Pengcheng his capital. (Records of the Grand Historian (Shiji), Annals 史記卷007 項羽本紀)
He made Duke Pei King Han and gave him Ba, Shu and Hanzhong, making Nanzheng his capital, and divided Guanzhong among three surrendered Qin generals. (Records of the Grand Historian (Shiji), Annals 史記卷007 項羽本紀)
They had been loyal while Rome was winning but turned to Carthage once the Scipio brothers' armies were wiped out (Livy, History of Rome (Ab Urbe Condita) 28.19)