The Battle of Baideng (白登之戰) was a military conflict between Han China and the Xiongnu in 200 BC. Han Dynasty of China invaded the territory of the Xiongnu in 200 BC attempting to subjugate them. However the Xiongnu united their forces under Modu Shanyu and surrounded the Han emperor Gaozu in Baideng. The siege was only relieved after seven days when the Han royal court, under Chen Ping's suggestion, sent spies to bribe Modu's wife.