present-day Pingliang, Gansu). Yang Qiu surrendered and was allowed to retain his former titles and remain in his domain to pacify the people there. Ma Chao retreated further west after his defeat at Tong Pass. Cao Cao pursued him to Anding Commandery but gave up on the pursuit after two months and headed back to Ye (in present-day Handan, Hebei) upon receiving news about unrest in northern China. He left Xiahou Yuan behind to defend Chang'an. About a year after Ma Chao rebelled against the Han imperial court, Emperor Xian issued a decree ordering the execution of Ma Chao's family members in Ye. After Cao Cao left, Ma Chao led the various tribes in the region to attack the commanderies and counties in Guanzhong, while the people responded to his call and joined him in the revolt. In 213, Ma Chao killed Wei Kang, the Inspector of Liang Province, and seized control of Jicheng () and forced Wei Kang's subordinates to submit to him. He took control of Liang Province. Wei Kang's former subordinates were unhappy with Ma Chao so they plotted to get rid of him. Later that year, they rebelled against him and succeeded in driving him out of Guanzhong. Ma Chao fled to Hanzhong, where he borrowed troops from the warlord Zhang Lu, and returned to attack those who drove him out of Guanzhong. He besieged Jiang Xu, Zhao Ang, Wang Yi, and their allies at Mount Qi (祁山; the mountainous areas around present-day Li County, Gansu) for about 30 days until reinforcements led by Cao Cao's generals Xiahou Yuan and Zhang He showed up and lifted the siege. Cao Cao's analysis of the battle After the battle, Cao Cao's officers asked their lord: "Earlier on, when the rebels were at Tong Pass, the north of the Wei River was not guarded. Why didn't you attack Pingyi (馮翊) from the east bank, and instead choose to defend Tong Pass and cross the river later?" Cao Cao replied, "The rebels were at Tong Pass. If I went to the east bank, they would definitely increase their defences at the fords and we wouldn't be able to cross over to the west. Hence, I chose to deploy our forces at Tong Pass so that the rebels would concentrate their defences on the south bank and lower their guard in the west. This was why our two generals (Xu Huang