north bank of the river as he foresaw that Zhuge Liang would attempt to seize the plains. When the other officers disagreed, Guo Huai said, "If Zhuge Liang crosses the Wei River and occupies those plains, his troops will have access to the mountains in the north. If they block the road through the mountains, it will cause fear and panic among the people living in the region. This isn't helpful to our State." Sima Yi agreed with Guo Huai and sent him to occupy the plains. While Guo Huai and his men were building a camp on the plains, they came under attack by Shu forces but managed to drive them back. Several days later, when Guo Huai received news that Zhuge Liang was planning to launch an attack in the west, his subordinates wanted to strengthen the defences in the west. Guo Huai was the only one who recognised that it was a ruse, and that Zhuge Liang was actually planning to attack Yangsui (陽遂; the area north of the Wei River in present-day Mei and Fufeng counties, Shaanxi). He was proven right later as the Shu forces attacked Yangsui at night. However, as Guo Huai had set up defences earlier, the Shu forces failed to capture Yangsui. Service under Cao Fang In 240, the Shu general Jiang Wei continued Zhuge Liang's aggressive foreign policy towards Wei and launched the first of a series of invasions of Wei. Guo Huai led Wei forces to repel the invaders at Longxi Commandery and forced them into the territory of the Qiang tribes. After Jiang Wei and his troops retreated back to Shu, Guo Huai followed up by attacking the Qiang tribes led by Midang (). He also managed to pacify more than 3,000 Di clans in the region and resettled them in the Guanzhong region. The Wei government promoted him to General of the Left () in recognition of his achievements. Resettling Xiongnu clans in Gaoping County Liang Yuanbi (), a Xiongnu leader in Liang Province, led more than 2,000 clans to submit to Wei rule. Guo Huai wrote to the Wei government, requesting permission for the Xiongnu clans to be resettled in Gaoping County (高平縣; present-day Guyuan, Ningxia), Anding Commandery (). He also established the office of the Commandant of Xichuan () to oversee their safety. For his efforts, Guo Huai was promoted to General of the Vanguard (),