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In 552, rival Liang Dynasty, in the aftermaths of the major rebellion by Hou Jing and Hou's death earlier that year, had two major claimants to its throne—Xiao Yi (Emperor Yuan of Liang), who controlled the central and eastern provinces, and Xiao Ji, who controlled the western provinces, both sons of the founding emperor Emperor Wu. Xiao Yi, under attack from Xiao Ji, requested aid from Western Wei—in the form of an attack to Xiao Ji's rear, against Xiao Ji's home province Yi Province (modern central Sichuan). Yuwen believed this to be a great opportunity for Western Wei to conquer the modern Sichuan and Chongqing region, but when he discussed the matters with the generals, most were in opposition. Yuchi, however, was supportive of the plan and advocated an immediate attack. Yuwen thus put him in command over six other generals to attack Xiao Ji's realm, and the attack was launched in spring 553. Yuchi quickly advanced to Xiao Ji's capital at Chengdu (成都, in modern Chengdu, Sichuan). Xiao Ji's army, which was then battling Xiao Yi near Xiao Yi's capital of Jiangling (江陵, in modern Jingzhou, Hubei), collapsed, and Xiao Ji was killed by Xiao Yi. After Yuchi had put Chengdu under siege for five months, Xiao Ji's cousin Xiao Hui (蕭撝) and son Xiao Yuansu (蕭圓肅), who were defending Chengdu, surrendered. The surrounding provinces also soon surrendered, and Western Wei had taken over Xiao Ji's domain. Yuwen made Yuchi the governor of Yi Province, in charge of 12 provinces centering Yi. In 554, six provinces were added to Yuchi's responsibility, for 18 provinces total. However, as Yuchi missed his mother deeply, and his mother was still at the capital Chang'an, Yuwen soon recalled him back to Chang'an.