Complex sentence: Initial minor invasions led by Xiahou Dun were repelled by Liu Bei of Xinye, who was a vassal of Liu Biao at the time, thus Cao Cao marched his armies south to personally conquer Jingzhou in the seventh month of 208.
Split into simpler sentences: Initial minor invasions led by Xiahou Dun were repelled by Liu Bei of Xinye, who was a vassal of Liu Biao at the time. Thus Cao Cao marched his armies south to personally conquer Jingzhou in the seventh month of 208.