8 events the sources record for this year, grouped by region.
What happened
China (6)
Li Shimin defeated Liu Heita on the banks of the Mingshui and recovered the prefectures and counties that had been taken. (Old Book of Tang (Jiu Tangshu), Annals 舊唐書 卷1 武德5年 3月)
In February 622, Liu Heida returns to attack along the Mingshui; when he reaches Lieren, Shimin, Prince of Qin, intercepts him with Qin Shubao and routs him. (Zizhi Tongjian (Comprehensive Mirror) 권190 622년 항)
In February 622 (Gengchen day), Duan Decao, commander of the Yanzhou march, attacks Liang Shidu's Shibao; when Shidu comes in person to rescue it, Decao routs him, and Shidu flees with sixteen horsemen. (Zizhi Tongjian (Comprehensive Mirror) 권190 622년 항)
In October 622 (Yichou day), Commander Daoxuan, Prince Zhuang of Huaiyang, fights Liu Heida at Xiabo, is defeated, and is killed by Heida. (Zizhi Tongjian (Comprehensive Mirror) 권190 622년 항)