The Goguryeo-Sui War was a significant military conflict initiated by the Sui dynasty to counteract territorial incursions by the Goguryeo kingdom, one of the Three Kingdoms of Korea. Following a series of skirmishes that escalated tensions in the region, Emperor Wéndi of Sui recognized the need for a decisive action. On this occasion, he ordered his youngest son, Yang Liang, to lead a formidable military campaign aimed at conquering Goguryeo. The operation was notable for its timing, as it unfolded during the Manchurian rainy season, a period typically fraught with logistical challenges for large-scale military campaigns due to adverse weather conditions.Yang Liang was supported by Gao Jiong, a capable co-prime minister who aided in strategizing the military approach. The Sui dynasty, eager to consolidate its influence and territorial holdings, prepared both a land army and a naval force for the operation. This ambitious endeavor reflected the broader Sui goals of unification and expansion, and it demonstrated the ambitious military aspirations of the dynasty. The campaign began a series of confrontations that would define Sino-Korean relations for years to come, ending in significant conflict and shaping the future of the Korean Peninsula's geopolitics.