He fended off four Sui campaigns by Emperors Wendi and Yangdi, including the great assault of 612, during which more than a million troops invaded Goguryeo territory.

[2] The Samguk sagi relates that Yeongyang was of unsurpassed charisma and had a magnanimous character, and "made it his undertaking to relieve the sufferings of the world and bring peace to the people".

At the same time, Yeongyang strengthened relations with the Khitan and Mohe tribes to the north, in the preparations for war against China begun by his father.

It was largely this affront, combined with Sui's own geopolitical ambitions to reestablish the hegemony enjoyed by the Han dynasty, that induced Wendi to launch a 300,000-men invasion of Goguryeo in 598.

In the meanwhile, Goguryeo attacked the southern Korean kingdoms Baekje and Silla in a failed bid to reclaim the Seoul region.