Du Ruhui was born into an official family, and his youth was eager to learn. During the great cause, Gao, assistant minister of the official department, attached great importance to his cleverness and resourcefulness, so he was appointed as a captain of Fuyang County (now Cixian County, Hebei Province). Seeing the political corruption in the Sui Dynasty, he thought that the position of county commandant was humble, so he abandoned his official position and returned to his hometown.
At the end of the 13th year of Daye (6 17), Li Yuan and his son led the army to conquer Chang 'an, and the Tang Dynasty was established the following year. Li Shimin, the king of Qin, heard that Du Ruhui was resourceful and asked Cao Jun to join the army. When the Tang regime was first established, officials should be stationed in various places. At that time, there were many talented aides in Qin Gong, and some of them had been transferred to serve. Fang said, "Du Ruhui is smart and brave, and he is a rare talent. If you want to build an imperial industry in the future, you must have this person's assistance. It's not a pity that everything else has been transferred, but the society seems to be gloomy. " Hearing this, Li Shimin immediately hit Tang Gaozu, asking her to stay in Qin Wangmi. From then on, Du Ruhui followed Li Shimin and became the core figure of Li Shimin think tank.
In August of the first year of Wude (6 18), Xue Ju, who was stationed in Longyou today, strengthened Mazhuang and took advantage of the unstable position of Li Tang regime to send troops to the east. Gaozu sent Li Shimin to lead the army to conquer, and Du Ruhui served as a strategist. After two battles, Tang Jun completely defeated the Western Qin forces and relieved the threat from the northwest. In order to reward Li Shimin for his meritorious military service, Tang Gaozu ordered him to host a festival in Shaanxi. Du Ruhui accompanied him by a very famous doctor, from Jianping County, and 300 households in the food city. Subsequently, the armies of Liu Wuzhou, Wang and other armed separatist forces continued to advance eastward, and Du Ruhui often accompanied them, taking the lead and winning the battle. He handles official business quickly and accurately, and is the most capable talent among his colleagues. In the fourth year of Wude (62 1), in October, Li Shimin set up a literature museum, recruiting talents and scholars, and studying literary works, with 18 bachelors. Du Ruhui was chosen as a bachelor.
With the consolidation and development of the regime in the Tang Dynasty, the battle for the throne was gradually launched between Prince Li and the King of Qin. Du Ruhui and Fang gave an idea to encourage him to pre-empt and launch a coup to get rid of Li Yuanji. Cheng Jian and Yuanji are also stepping up their planning, intending to divide and disintegrate the backbone of Qin Gong. He knew that "the only thing to be feared in Qin Gong is society, such as Huihefang" (1) So he told Gaozu that the government agency was not conducive to the court. High-impedance ordered the people in the palace and the people in the club to be driven out of Qin Gong, and they were not allowed to serve the people of Li See privately in the future. When Li Shimin made up his mind to fight with the Fuehrer for the last time, he sent Wei Chijingde to the convenor and Du Ruhui's family to discuss. Du Ruhui disguised himself as a Taoist and followed Sun Chang into Qin Gong. After careful arrangement, in the early morning of June 4th, the 9th year of Wude (626), Li Shimin led Du Ruhui and other soldiers to launch the famous "Xuanwu Gate Incident", which killed Li and Li Yuanji and wiped out political opponents. Li Shimin is the Crown Prince and worships Ruhui as the prince's left illegitimate child.
In August of the same year, Tang Gaozu was forced to abdicate and Li Shimin became emperor. Du Ruhui worked with counselor Li Shimin for many years, especially in the process of plotting a coup and helping Li Shimin seize the throne. He was promoted to be the minister of war, named Cai Guogong, and there were 65,438+0,300 households in the food city. In the second year of Zhenguan (628), he took this officer as a proofreader, assistant, branch minister and director of horse affairs for East officers and soldiers. In February of three years, he was promoted to the right assistant of Shangshu, still in charge of selecting officials, and jointly in charge of state affairs with Fang. In that year1February, he resigned due to illness.
At the beginning of his reign, Li Shimin made great efforts to carry out a series of political reforms. As Li Shimin's main adviser, Du Ruhui played an important role. All major military and political events participated in the consultation, which played an important role in assisting Emperor Taizong to establish the imperial edict system, select officials and establish the legal system. At that time, the ruling class learned the lessons from the demise of the Sui Dynasty and adopted some preferential policies for farmers, which made the productive forces develop, the national political situation stable and the economy gradually prosperous, and created the famous "chastity rule" in history. It was a famous phenomenon at that time that Fang was good at planning and Du Ruhui was good at judging.
At the beginning of the fourth year of Zhenguan (630), Du Ruhui was seriously ill, and Taizong personally visited his home. In that year1February, Du Ruhui died of illness at the age of 46. Emperor Taizong abandoned the court for three days to show his condolences. And ordered Yu Shinan to write an inscription for it. I sent a letter to the same three divisions of Kaifu Instrument, which was added as Sikong and renamed Lai Guogong.