What is the historical significance of the Siege of Baideng in the Han Dynasty?

Liu Bang's 300,000 founding army really couldn't defeat the 400,000 cavalry of the Hun King Maodun Shanyu.

At that time, the Central Plains had just experienced the Chu-Han War and were so poor that even Liu Bang's carriage could not get together four horses of the same color. The Huns were in great power. After Maodun Shanyu killed his father and succeeded to the throne, he began to expand externally. After defeating the King of Donghu, he immediately annexed Loufan and the King of Baiyang Henan (another tribe of the Xiongnu, living south of Hetao), and recovered the Xiongnu land captured by Meng Tian, ??as well as the Han Dynasty's Na (southeast of Guyuan, Ningxia today), Fu Shi (now southeast of Yulin, Shaanxi) and other counties. And they invaded and plundered the Yan, Dai and other places of Han Dynasty. Attacking the Yuezhi to the west, the Dingling, Hunyu, Qushe, Gekun, Xinli and other tribes in the north and northwest surrendered to the Huns. In 201 BC, King Xin of Han was forced to surrender to the Huns. In 200 BC, Liu Bang, the great ancestor of the Han Dynasty, personally led a 320,000-strong army to conquer Baideng (now northeast of Datong, Shanxi Province) and was besieged for seven days and nights by more than 400,000 cavalrymen of the Xiongnu Modun Shanyu. Only later did he use a trick to escape.

After the Battle of Baishan Mountain, Liu Bang realized that the Han Dynasty was too weak and the Huns were too strong. Therefore, Liu Jing's suggestion was adopted and the "marriage policy" was implemented towards the Xiongnu. The Han clan's daughter was married to the Chanyu, and a certain amount of property was given as a gift and the customs market was opened to allow the people of both sides to trade. Later emperors Wen and Jing also followed the marriage policy to recuperate. This strategy is to hide one's strength and bide one's time, but in essence it is to secretly accumulate strength and prepare for a decisive battle.

During the peace period, the Xiongnu continued to expand and become stronger. The Xiongnu attacked the Yuezhi to the west. After the old Shanyu succeeded to the throne, he defeated and killed the Yuezhi king, forcing the Yuezhi to migrate to the Western Regions. Then the Huns took control of the Western Regions. Collect taxes and manpower from the Western Regions. Continue to attack Han Dynasty counties in the south.

The Han Dynasty accumulated strength through peace and marriage, and finally defeated its powerful enemy. By the time of Emperor Wu of the Han Dynasty, after nearly 70 years of recuperation, the Western Han Dynasty had greatly enhanced its economy and national strength. It shifted from strategic defense to strategic offensive against the Xiongnu, and launched three major wars: the Battle of Henan (also called the Battle of Monan), the Battle of Hexi, The Battle of Mobei. At this time, it was the reign of Yi Zhixie Chanyu. In the second year of Yuanshuo (127 BC), Wei Qing was sent to occupy the Hetao area. In 124 BC, Wei Qing and others were sent to defeat the invading 90,000 Huns cavalry. In 121 BC, Huo Qubing was sent to seize the prosperous Hexi Corridor. The Han surrender general Zhao Xin persuaded the Xiongnu to move the royal court to Mobei to avoid being attacked. With the geographical advantage, he could defeat the Han army while waiting for work. In 119 BC, Wei and Huo attacked Mobei from east to west. Huo Qubing attacked the Xiongnu in Langjuxu Mountain in Mongolia, and Wei Qingdong Road swept away the Xiongnu royal court. King Youxian led more than 40,000 people to surrender to the Han Dynasty. The Han army captured more than 70,000 people. Yizhixie Chanyu and King Zuoxian escaped with a few people. The period of decline of the Xiongnu Kingdom lasted from Yizhixie Chanyu to Huhanxie Chanyu, and went through 18 Chanyus, from the reign of Emperor Wu of the Han Dynasty to the third year of Emperor Jianzhao of the Han Dynasty (36 BC) when the Zhizhi Chanyu was destroyed.

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