In the last year of the Sui Dynasty, the world was in chaos, and the crowd was in full swing, and finally Li Yuan seized the world, thus establishing the Tang Dynasty. However, in the beginning, the strongest force was not Li Yuan, but Li Mi, the leader of the Wagang Army. At that time, Li Mi had 300,000 troops, known as millions, and not only had a number of fierce generals such as Qin Qiong, Cheng Yaojin, and Shan Xiongxin, but also controlled Luokoucang. It can be said that Li Mi was a strong soldier and a strong soldier, and even Li Yuan took the initiative to tie the knot, but in the end he failed to become emperor and went to defeat.
First, they were attacked on all sides and their strategic positions were very poor
When Li Mi was at his strongest, he was said to have millions of people, but his main base was in the Henan region. In ancient China, geographical advantage had a great influence on a regime, and since ancient times, the Guanzhong region was easy to defend and difficult to attack, so many dynasties rose from Guanzhong. The terrain of Henan is flat, so there is no danger to defend; in addition, Henan was called Zhongzhou in ancient times, and it is accessible in all directions, and although the traffic is convenient, it is attacked on all sides.
To the east of Li Mi was Wang Shichong, who was still in the Luoyang region, and Yang Tong, the grandson of the Sui Emperor, was made emperor, and although his army was less than Li Mi's, he had a strong economic strength and a lot of money and grain. To the north of Li Mi was Dou Jiande, who had divided Hebei, and he also had more than 200,000 troops under his command, and his strength should not be underestimated. To the south of Li Mi was Xiao Milling, who occupied a vast area south of Jingchu and "won 400,000 soldiers". Although Li Mi's strength is very strong, he is surrounded by strong enemies, which limits Li Mi's development.
Second, kill Zhai Rang and alienate himself internally
The original leader of the Wagang army was Zhai Rang, and Li Mi had originally come to trust him, but Zhai Rang found that Li Mi's talent surpassed his own, so he gave up the position of leader to Li Mi. However, after Li Mi became the leader, he was narrow-minded and selfish, and actually designed to kill Zhai Rang at a banquet. After Zhai Rang's death, although Li Mi had no rivals, the internal generals were thus alienated, and "the secret general Zuo began to have doubts about himself."
Later, in the Battle of Yaoshan, Li Mi led his army to a decisive battle with Wang Shichong, and at the critical moment, Shan Xiongxin did not move and refused to rescue him. After Li Mi's defeat, he originally wanted to return to Tiger Prison, but Shan Xiongxin, Feng Yuanzhen and others led their troops to directly surrender to Wang Shichong. Li Mi wanted to go to Xu Maogong, but he feared that something would change, after all, Xu Maogong was Zhai Rang's old subordinate. Li Mi killed Zhai Rang by disgraceful means, directly undermining internal unity and causing the Wagang army to fall apart.
Third, the decision-making errors, the strength is seriously damaged
In 618, Li Mi defeated Wang Shichong at the Battle of Luoshui, and his reputation reached its peak, and even Dou Jiande of Hebei sent someone to ask Li Mi to be proclaimed emperor. Under Li Mi's powerful offensive, the eastern capital Luoyang was already in jeopardy. However, at this time, Li Mi asked Yang Tong, the king of Yue, to surrender. Originally, Yu Wenhua and led more than 100,000 troops to the north to attack Liyang. Li Mi was worried about being attacked by the enemy on his belly and back, so he submitted to Yang Tong, the king of Yue, at that time, Wang Shichong's troops lacked food, but they had a lot of money, so the two sides traded.
Although Li Mi exchanged money, he gave grain to his enemies. After defeating Yuwen and later, the strength of the Wagang army was seriously damaged, and Wang Shichong used this time to fight fiercely. After that, Wang Shichong took the initiative to provoke a war and completely defeated Li Mi in the Battle of Yaoshan. Since then, the Wagang army has fallen apart, and Li Mi, who is cornered, enters guanzhong and defects to Li Yuan. In 619, Li Mi planned to betray the Tang Dynasty, and was eventually killed, and the only general who died with him was Wang Bodang.
References: 1. Old Book of Tang; 2. New Book of Tang; 3. Zizhi Tongjian