Emperor Wen of Sui
In 598, Emperor Wen of Sui collected an army of 300,000 troops to defend the pass. He gave 200,000 troops to Yang Liang who is the fourth son of Emperor Wen and 100,000 marines to Zhou Luohou. However, after constant ambushes combined with the roughness of the sea waves, in June 598, the Sui army started to retreat.