 Silla thus unified most of the Korean peninsula in 668, but the kingdom's reliance on Tang China had its price.Tang China attempted to impose its rule over the entire Korean peninsula, but Silla, aided by Goguryeo and Baekje refugees, forcibly resisted and expelled Tang.However, Silla's unification of the Three Kingdoms of Korea was short-lived because the former Goguryeo general Dae Joyeong led remnants of Goguryeo, united with the Mohe people, and established Balhae, a successor of Goguryeo.