King Yeongyang, born as Go Won, was the eldest son of King Pyeongwon. He ascended the throne in 590 AD during a time of immense geopolitical shift as the Sui Dynasty unified China and expanded its influence toward the east.
Recognizing the Sui as a major threat, he took a bold and preemptive approach. In 598 AD, he led 10,000 Mohe cavalry to attack the Sui border regions in western Liaonying. This act of defiance provoked Emperor Wen of Sui to launch the first major invasion against Goguryeo.
Throughout his reign, he oversaw the defense of the kingdom during four separate Sui campaigns. He placed great trust in talented generals like Eulji Mundeok, whose strategic brilliance at Salsu in 612 AD dealt a fatal blow to the Sui military.
Despite the immense pressure and repeated invasions, King Yeongyang refused to submit. He maintained a sophisticated diplomatic game, nominally offering peace to buy time while reinforcing his fortresses. His victory over the Sui ensured Goguryeo's survival and accelerated the collapse of the Sui Dynasty.