In AD 938, the Vietnamese lord Ngô Quyền defeated the forces of the Chinese Southern Han state at Bạch Đằng River and achieved full independence for Vietnam after a millennium of Chinese domination. Renamed Đại Việt ("Great Viet"), Vietnamese society enjoyed a golden era under the Lý and Trần dynasties. During the rule of the Trần Dynasty, Đại Việt repelled three Mongol invasions. Meanwhile, the Mahāyāna branch of Buddhism flourished and became the state religion. Following the 1406–7 Ming–Hồ War, which overthrew the Hồ dynasty, Vietnamese independence was interrupted briefly by the Chinese Ming dynasty, but was restored by Lê Lợi, the founder of the Lê dynasty. The Vietnamese dynasties reached their zenith in the Lê dynasty of the 15th century, especially during the reign of Emperor Lê Thánh Tông (1460–1497). Between the 11th and 18th centuries, Vietnam expanded southward in a process known as ("Southward expansion"), eventually conquering the kingdom of Champa and part of the Khmer Kingdom.