At the end of Emperor Yang Di's great career, Li Ji was only 17 years old. Seeing the chaos in the world, he joined Zhai Rang's army nearby. He persuaded Zhai Rang, "This neighborhood is your hometown and my hometown folks, so it is not suitable for intrusion. Song and Zheng are close to the river and often have business dealings. It is very convenient to rob officials' private money there. " Zhai Rang called it good, so he robbed public and private property on the canal. There is no shortage of people if you have money. Soon, the soldiers will flourish. Zhang Xutuo, a famous soldier in Sui Dynasty, crusaded against Zhai Rang who fled in fear. Li Ji stopped fighting in Sui Jun with more than twenty thousand people, but was defeated by Zhang Xutuo and defeated the loyalist. At that time, Pushan Gong Shi Biao participated in the rebellion in Yang Xuangan and fled after defeat. Both Li Ji and Wang Bodang know that Shi Biao is a hero in the world. Together, they persuaded Zhai Rang to give priority to Shi Biao in order to buy people's hearts and expand their influence.
The Sui Dynasty ordered the king to crusade against Shimi. Li Shiqi refused to fight several times, and defeated the king many times on both sides of the Luoshui River with strange tricks, so he was named Donghai County in Feng Li. At that time, floods occurred in Henan and Shandong, and there were hungry people everywhere. The Sui Dynasty helped the poor and starved tens of thousands of people every day. Li Ji said to Li Mi, "There is a great chaos in the world, and this is because of hunger. If you capture Liyang Guocang, great things can be achieved. " After hearing this, Shi Biao sent Li Ji and five thousand people to cross the Yellow River voluntarily to attack the defenders of the Sui Dynasty in Li Yangcang. On the same day, he conquered and opened a warehouse to recruit people to take whatever they want. Within ten days, more than 200,000 soldiers were recruited. More than a year later, Emperor Jiangdu and Yang Dong, King of Yue, pardoned Shi Biao in Luoyang and Tokyo, made him Wang Wei and worshipped him as Qiu. The Sui Dynasty also named Li as General Wuhou and ordered them to attack together. Li Ji guarded Liyang, the granary city, and Yu Wenhuaji led troops to attack the city on all sides. The situation is critical. Li Ji dug a tunnel from the city, suddenly appeared outside the city, defeated Yu Wenhuaji and escaped.
In 6 19 AD, Shimi returned, was defeated by the king, and assembled the remnant troops to return to the Tang Dynasty. Li Mi's original territory extends to the sea in the east, the Yangtze River in the south, Ruzhou in the west and Weijun in the north, all of which are occupied by Li Ji, with no specific ownership. Li Ji told Guo Xiaoke that it has a long history. "Gong Wei has always belonged to Datang, and now the people's land here belongs to Gong Wei. If I give them the above table, I will profit from the master's failure and keep the wealth for myself. I think this is shameful. Now it is necessary to record the names, figures, military and civilian accounts of each county in detail and report them all to Gong Wei, so that Gong Wei can devote himself to the court. This is the contribution of Gong Wei. "
So he sent a messenger to report to Shi Biao. When the emissary first arrived at the imperial court, Tang Gaozu heard that Li Ji didn't set a watch, but just sent a letter to Shi Biao, which was very strange. When the original intention was conveyed to Li Yuan, Li Yuan said happily, "Xu thanked the host for his kindness and declined his contribution. He is indeed a pure and honest courtier. " Under the imperial edict, he was appointed as the general manager of Liyang, the pillar country, and took charge. Soon, General You Wuhou was appointed, renamed Cao Guogong, given the surname Li, and given 50 hectares of fertile land as the first residence of the upper class. His father, Gary, was made King Yin Ji, and Gary resolutely resigned from the throne, so he changed his country name to Duke Shu, and was appointed as "a constant servant of the three Qi" and "a secretariat of Ling Zhou". He was ordered to lead the troops of Henan and Shandong provinces against the king. When Shi Biao rebelled against the imperial court and was killed, Li Yuan sent messengers to tell Li Ji about Shi Biao's rebellion against the imperial court, because Li Ji had worked for him in the imperial court.
In 62 1 a.d., he followed Ping Sifang to crusade against the king and won many battles. After seizing the land, he went east to Hulao Pass and asked for Hulao Pass with Zheng Lianbing. Anyway, they ambushed the army at night, occupied Hulao Pass and captured Hangben, the state secretariat of Zheng. He followed to pacify Dou Jiande, surrender the king, reorganize the army and return to Korea. On merit, Li Shimin is a general, and Li Ji is the next general. Li Ji and Li Shimin, dressed in glittering armor, went to the ancestral temple in a carriage. Li Ji's father and Pei Ju entered Korea from Mingzhou together. Tang Gaozu was very happy to meet them and restored Gary's official title. Li Ji followed Li Shimin to defeat Liu Heita and Xu Yuanlang, and was promoted to Left General. Soon, Xu Yuanlang occupied Yanzhou and rebelled again. In July, the court named Li Ji as the secretariat of Yuzhou. Soon, July was captured, the head was beheaded in the court, and Yanzhou was pacified.