At the Battle of Bạch Đằng River in 938 the Vietnamese forces, led by Ngô Quyền, defeated the invading forces of the Southern Han state of China and put an end to centuries of Chinese imperial domination in Vietnam. It took place at the Bach Dang River, near Halong Bay in northern Vietnam.
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Ngô Quyền anticipated this plan and brought his army to the mouth of the river. He had his men plant a barrier of large poles in the bed of the river. The tops of the poles reached just below the water level at high tide and were sharpened and tipped with iron. When Liu Hongcao appeared off the mouth of the river, Quyen sent out small, shallow-draft boats at high tide to provoke a fight and then retreat upriver, drawing the Chinese fleet in pursuit. As the tide fell, the heavy Chinese warboats were caught on the poles and lay trapped in the middle of the river, whereupon they were attacked by Ngô Quyền's forces. More than half the Chinese were drowned, including Liu Hongcao. When news of the battle reached Sea Gate with the survivors, Liu Yan wept openly. He collected what remained of his army and returned to Canton.
This victory ended China's long domination of Vietnam and began a period of Vietnam's independence until the conquest by Ming China. Ngô Quyền's tactic would later be copied by Trần Hưng Đạo in a battle at Bạch Đằng River against the Mongols in 1288.