In July 207 BC, Xiang Yu and Zhang Handan set up an alliance south of Huanshui and on the ruins of Yin Shang, and Zhang Handan surrendered to Xiang Yu.
At this time, Liu Bang led an army into Nanyang County, besieged the city of Yang, and did not ke. Coming west to the capital of Nanyang, Wancheng, the city is high and wide, and there is no way to do anything. According to this rhythm, Liu Bang would be trapped in Nanyang County, and Xiang Yu would not hurry to enter Guanzhong, leaving Liu Bang with little time.
With Xiang Yu's east wind beckoning Zhang Handan, Liu Bang turned to negotiate with Nanyang Taishou. Both sides are willing to negotiate peace, and the negotiations are going well. Liu Bang enfeoffed Nanyang as the Marquis of Yin, and his protégé Chen Hui became a thousand households, and the two remained in Wancheng.
Wancheng was originally the capital of Nanyang, with dozens of cities, a large population, and abundant grain. Liu Bang took wancheng, the Chu army went to all parts of Nanyang, the autumn did not violate, the cities looked forward to the wind surrender, changed the flag, and the Qin army changed into the Chu army.
Liu Bang's next step was to enter Guanzhong before Xiang Yu, referring to the historical Qin-Chu War and the Battle of Danyang during the Warring States period, similar to the current situation.
In 312 BC, at the Battle of Danyang, the State of Chu took the initiative to attack, and the northern route led more than 200,000 troops from Jingcui of the Shangzhu State into Korea, intending to attack Hangu Pass, and the Prince of Qin led an army of 150,000 to Korea; the general Qu Cai led an army of 150,000 to conquer Wuguan and entered the land of Shangyu, with a momentum of rainbows, and the Qin general Wei Zhang led an army of 80,000 to attack; the southern route was Ling Yin Zhaoyu led 100,000 troops to attack Hanzhong, and the Qin general Gan Mao led an army of more than 20,000 people to attack.
In terms of troop strength, the Chu army was 450,000, the Qin army was 250,000, and the Advantage of the Chu Army was obvious. The Chu kingdom is known as a million with armor, and it is indeed worthy of the name. At that time, the Qin general Sima Que led an army into Sichuan to quell the rebellion, and the Qin state was overstretched, which was one of the reasons why the Chu state chose this time point to start a war.
In this battle, the Chu army of Qu Cai in the middle of the Chu State initially attacked rapidly, and Wei Zhang's 80,000 Qin army and Qu Qi's 150,000 Chu army faced off at the land of Shangyu, and each side used the terrain to build a barrier. Later, Wei Zhang used five thousand odd soldiers to burn down the Chu army's grain points. On the way to withdraw his troops, because the terrain was unfamiliar, more than 30,000 people were completely annihilated. The Chu army threw away its armor and armor, and Qu Qi was caught in the army and fled all the way to the vicinity of Danyang in Nanyang County. Wei Zhang sent a cavalry force of the Qin state to venture around to Danyang to ambush and capture Qu Qi.
The Chu army's middle road collapsed, and the north and south roads had to collect troops. In this battle, the Chu army had 150,000 people, 80,000 killed, the generals Qu Qi and Qiu General Feng Hou were captured, and more than 70 middle and high-ranking generals were either killed or captured.
The Battle of Danyang brought Liu Bang a lot of enlightenment, which was a textbook war, telling Liu Bang that he could divide his troops into three ways to attack the Qin army. The Northern Route Army left Xiang Yu, and since it had surrendered to Zhang Handan, the soldiers were strong enough to attack Hangu Pass. The middle road was Liu Bang himself, and Qu Cai quickly conquered Wuguan, which made Liu Bang's self-confidence burst. It is only after conquering Wuguan that we must not take it lightly, and there will definitely be hard battles to be fought later. The southern road needs to send a partial division to attack Hanzhong, forming more pressure on Guanzhong and effectively containing the opposing forces.
Who will go to the Southern Route Army? Lü Ze and other friendly troops would not go, they could follow Liu Bang to clean up the war, and fight the Qin army head-on, which was certainly not willing. Liu Bang's army of Xincheng Junli Shang initially numbered 4,000, and after the expansion of Yingchuan County and Nanyang County, it reached more than 6,000 people, which was the strongest force in Liu Bang's own army. Liu Bang then ordered Li Shang to lead his troops and horses to go up against the Han River and attack Hanzhong County.
Liu Bang roughly copied the pattern of the Battle of Danyang, attacking Hangu Pass for Xiang Yu; Liu Bang attacking Wuguan; and Li Shang attacking Hanzhong.
Liu Bangbing approached Wuguan, sent Ningchang into the pass, and went to Xianyang to negotiate with Zhao Gao.
At this time, Zhao Gao forced the death of Qin II, took the Chuanguo Jade Seal and the Clan Bi, put them on his body, and sent people to summon hundreds of officials to the court and proclaim himself the King of Qin.
Zhao Gao killed the eighteen sons and descendants of Qin Shi Huang, and the Qin people hated that they could not eat their flesh, and none of the ministers listened. Zhao Gao was furious and asked Ning Chang to go back and tell Liu Bang that he Zhao Gao opened the gate of Wuguan and let the Chu army enter the pass, on the condition that the guanzhong be divided equally.
In order to stabilize the situation, Zhao Gao temporarily made his servant The Infant as the King of Qin, pretending to be obedient to the wishes of the Qun subjects, and when Liu Bang agreed to divide Guanzhong equally, he killed the infant. Who expected that after five days, he killed Zhao Gao in the Zong Temple. He ordered Zhao Gao's corpse to be split and displayed to the public, and to exterminate his three tribes, and everyone was happy at the time.
The General of Wuguan Shou was originally a local piracy Zhu Pu, as a close associate of Zhao Gao to guard Wuguan, he had zhao Gao's army order switch to let the Chu army in, who dared to question. After a few days of hearing that Zhao Gao was dead, he immediately fled with his cronies and belongings.
At the same time, another partial division, Xin Chengjun Lishang, conquered Xunguan in Hanzhong and was marching south to Zheng.
In ancient times, Hanzhong was divided into East and West Hanzhong, the Western Han Dynasty was the ancient Chu Kingdom, and the homeland of the Chu Dynasty was today's Han Zhong, and the Eastern Han Dynasty was the Ancient Yong Kingdom, which was destroyed by the Chu State, roughly in the area of present-day Shiyan and Fangling. In order to prevent the State of Chu, the Yong State built the fortress of Xunguan (present-day Shiyanxun County, Hubei) on the Eastern Han River, which was the first barrier for Nanyang to enter the Eastern Han Dynasty.
During the Warring States period, the State of Qin occupied the Western Han Dynasty, and the State of Chu occupied the Middle Of the Eastern Han Dynasty. The State of Qin marched east along the Han River and could attack the Eastern Han Dynasty of the State of Chu, and vice versa. The State of Qin was at the junction of the East and West Hanzhong, where the Xunshui and Han rivers converged, and built the fortress of Xunguan (present-day Xunyang County, Ankang, Shaanxi) to block the Chu army from entering Southern Zheng in the west, similar to Wuguan blocking the Chu army from entering Guanzhong.
During the Qin Dynasty, most of these customs that were not border areas were abandoned and there were very few troops stationed. Li Shang's division of more than 6,000 tigers and wolves, marching west to break through Xun Pass and Xun Pass, and capture Nanzheng is also just around the corner.
In October, outside xianyang city, the Chu army was full of armored soldiers, brilliant jinge, ten thousand wisps of dust, and murderous qi.
The prince of Qin rode in a white horse, wore a wide white silk coat, tied a white bond around his neck, and surrendered to Liu Bang at the side of the Xuandao Road with the jade seal of the country and the clan bi.
At this time, Xiang Yu was still in Hebei, busy dealing with the contradictions of the princes' armies, coupled with the drag of 200,000 Qin troops, it can be said that the first to strike and then the last, lagging behind Liu Bang into Guanzhong, laying the groundwork for the follow-up Chu-Han War.