The Battle of Salsu was a major battle that occurred in the year 612 during the second campaign of the Goguryeo–Sui War between Goguryeo of Korea and Sui of China. Goguryeo won an overwhelming victory over the numerically superior Sui forces at Salsu River.
^ abLee, Ki-Baik (1984). A New History of Korea. Cambridge, Massachusetts: Harvard University Press. p. 47. ISBN067461576X. "Koguryŏ was the first to open hostilities, with a bold assault across the Liao River against Liao-hsi, in 598. The Sui emperor, Wen Ti, launched a retaliatory attack on Koguryŏ but met with reverses and turned back in mid-course. Yang Ti, the next Sui emperor, proceeded in 612 to mount an invasion of unprecedented magnitude, marshalling a huge force said to number over a million men. And when his armies failed to take Liao-tung Fortress (modern Liao-yang), the anchor of Koguryŏ's first line of defense, he had a nearly a third of his forces, some 300,000 strong, break off the battle there and strike directly at the Koguryŏ capital of P'yŏngyang. But the Sui army was lured into a trap by the famed Koguryŏ commander Ŭlchi Mundŏk, and suffered a calamitous defeat at the Salsu (Ch'ŏngch'ŏn) River. It is said that only 2,700 of the 300,000 Sui soldiers who had crossed the Yalu survived to find their way back, and the Sui emperor now lifted the siege of Liao-tung Fortress and withdrew his forces to China proper. Yang Ti continued to send his armies against Koguryŏ but again without success, and before long his war-weakened empire crumbled."
^ abNahm, Andrew C. (2005). A Panorama of 5000 Years: Korean History (Second revised ed.). Seoul: Hollym International Corporation. p. 18. ISBN093087868X. "China, which had been split into many states since the early 3rd century, was reunified by the Sui dynasty at the end of the 6th century. Soon after that, Sui China mobilized a large number of troops and launched war against Koguryŏ. However, the people of Koguryŏ were united and they were able to repel the Chinese aggressors. In 612, Sui troops invaded Korea again, but Koguryŏ forces fought bravely and destroyed Sui troops everywhere. General Ŭlchi Mundŏk of Koguryŏ completely wiped out some 300,000 Sui troops which came across the Yalu River in the battles near the Salsu River (now Ch'ŏngch'ŏn River) with his ingenious military tactics. Only 2,700 Sui troops were able to flee from Korea. The Sui dynasty, which wasted so much energy and manpower in aggressive wars against Koguryŏ, fell in 618."