Zhenguan is the era name of Emperor Taizong of Tang Dynasty Li Shimin, from the "Yi Zhi ZhiXia": "The Way of Heaven and Earth, Zhenguan also." It means to show people the right way. In the 23 years of Zhenguan, the Tang Dynasty, with the joint efforts of Li Shimin's subjects, was politically clear, economic development, and national strength continued to grow, and finally achieved the ideal situation of great rule under the heavens, known in history as the "rule of Zhenguan".
According to the Tongdian records, after the great turmoil in the last years of the Sui Dynasty, the population of Tang Wude (Tang Gaozu Li Yuannian) was only more than 2 million households. However, after 23 years of development of Zhenguan, by the third year of Emperor Gaozong of Tang (652), the population had increased to 3.8 million households. It can be seen from this that the efforts of Li Shimin's 23 years of reign have been fruitful.
In the 23 years of Zhenguan, the Tang Dynasty not only achieved domestic development, but also made great achievements in foreign relations. It can be said that internal governance and external security have laid a solid foundation for the Kaiyuan prosperous era during the Tang Xuanzong period. However, what opened its magnificent chapter in such a great rule was the words "bloody rain and bloody wind, desperate to take risks".

[There was a bloody rain in front of Xuanwu Gate, and three days later Li Shimin was made crown prince and ascended the throne two months later as emperor]
The brotherly wall has always been an important drama in the court battles in the history of the dynasty. This was evident at the beginning of the establishment of the Tang Dynasty. Li Yuan, the emperor of Tang Gaozu, had many children, and his wife Dou Hui bore him four sons, Li Jiancheng, Li Shimin, Li Xuanba, and Li Yuanji. Among them, Li Xuanba died before Li Yuan raised an army, so after Li Yuan became emperor of Tang, his sons were left with three brothers, Li Jiancheng, Li Shimin, and Li Yuanji.
After the establishment of the Tang Dynasty, Li Jiancheng was made crown prince according to the order of the elder and the youngest. Li Shimin and Li Yuanji, one was crowned the King of Qin, and the other was crowned the King of Qi. As for the beginning and end of Li Yuan's uprising, this article will not dwell on and discuss too much. After all, more than a thousand years of time, I don't know how many facts have been drowned. But one thing is certain, that is, Li Shimin's military achievements.
In the Tang Dynasty, Sui Dynasty, and later large and small wars to unify the whole country, Li Yuan's son Li Shimin's military merit was the greatest. From 618 onwards, Li Shimin personally participated in three major battles.
First, the Battle of Qianshuiyuan destroyed the Western Qin forces of Xue Ju and Xue Rengao; second, it defeated Song Jingang and Liu Wuzhou and consolidated the northern part of the Tang Dynasty; and then the Battle of Tiger Prison, which annihilated Wang Shichong, who had divided Henan, and Dou Jiande, who had divided Hebei, in one fell swoop. Especially in the Battle of Tiger Prison, When Li Shimin's class returned to Beijing, he was warmly welcomed by the chang'an soldiers and civilians. With the support of these three major battles, Li Shimin's prestige is getting higher and higher.
Although Li Shimin had always been given the title of Emperor for his merits, later the existing official positions in the imperial court were sealed to the end, and Li Yuan simply created a "General of Heavenly Strategy" to him. Admiral Tiance was above the kings, second only to the emperor and the crown prince. However, Li Shimin not only had military achievements, but also gathered a lot of capable military generals around him at that time. Such as Fang Xuanling, Wei Chigong and others. Therefore, on these basis, there is some dissatisfaction with the eldest brother Li Jiancheng being made crown prince Li Shimin.
Li Shimin was dissatisfied with Li Jiancheng's becoming crown prince, while Li Jiancheng, who had become a prince, was jealous of his brother's military exploits. Therefore, at the beginning of the establishment of Datang, it ushered in a struggle between brothers for reserves. This battle was not only a battle of wits between the two brothers Li Jiancheng and Li Shimin, but also a contest between two political groups with the prince and the king of Qin as the core.
It is true that Li Jiancheng's merits in battle are inferior to Li Shimin's, but it cannot be judged that Li Jiancheng is a mediocre talent. To this end, the modern historian Mr. Chen Yinke made a fair remark, saying: When Emperor Gaozu raised an army in Taiyuan, Li Jiancheng and Emperor Taizong each led an army. As well as the crown prince, the bureaucrats he used, such as Wang Jue and Wei Zhengzhi, who were later the famous ministers of the rule of Zuocheng Zhenguan, can be seen that Li Jiancheng was also a man of intelligence.
To be fair, Li Jiancheng and Li Shimin should be evenly matched. At that time, Li Jiancheng also gathered a lot of fierce generals and strategists around him, and there was also the help of the fourth brother Li Yuanji. However, in this court infighting, the first crown prince of the Tang Dynasty finally fell into a fiasco. For this reason, we can only use the Mandate of Heaven to excuse Li Jiancheng.
On July 2, 626, Li Shimin, at the instigation of his generals, finally made up his mind to kill the crown prince Li Jiancheng and the Qi king Li Yuanji. After consulting with Fang Xuanling, Changsun Wuji, Wei Chigong and others, Li Shimin set up an ambush at Xuanwu Gate and prepared to preemptively attack. A bloody rain was inevitable, and the first palace coup of the Tang Dynasty, the "Xuanwumen Change", was immediately staged.
In fact, at that time, Li Jiancheng and Li Yuanji had already sensed that something was wrong when they approached the Xuanwu Gate, but in the end they could not escape the killing of their brothers. During the Xuanwumen Rebellion, Li Jiancheng and Li Yuanji were shot and killed, and their sons were all killed. This was the first coup d'état of datang, and it was also a bloody, violent and elaborate massacre.
Three days after the Xuanwumen Rebellion, Li Shimin became the new crown prince of the Tang Dynasty, and two months later ascended the throne as emperor for Emperor Taizong of Tang.
[The Turks in the Tang Dynasty took the opportunity to send troops, and Tang Taizong took a risk at the time of the thousand guns]
The xuanwumen rebellion ended the feud between Li Jiancheng and Li Shimin's brothers, and the Qin wang clique led by Li Shimin won a complete victory. But soon after Li Shimin ascended the throne, the Turks in the north attacked with an army of 100,000.
The Turks were a nomadic people in northern China at that time, and they developed and grew at the end of the Sui Dynasty. At the beginning of the establishment of the Tang Dynasty, not only the ethnic minority tribes in the north were subordinate to the Turks, but even many of the central plains were dependent on the Turks. When Li Yuan raised an army, he also married the Turks. Therefore, the Turks at that time had the ambition of the Xianbei Tuoba clan and wanted to enter the Central Plains.
Unfortunately, those Central Plains separatist forces that were once dependent on the Turks were later eliminated by Li Tang one by one. The power of the Turks was weakened to some extent, so the dream of entering the Central Plains was naturally stranded. However, the change of Xuanwumen within the Tang Dynasty in 626 gave the Turks hope.
At that time, the Turks had split into east and west, and the Eastern Turks were in a period of great power. Learning that there was a coup d'état within Li Tang, the Eastern Turk Jieli Khan sent 100,000 troops to raid the Tang Dynasty, and he wanted to take advantage of the unstable regime of the new Central Plains Dynasty to replace it.
The 100,000-strong Turkic army first opened a gap from JingZhou (泾州, in present-day northern Jingchuan, Gansu), and then marched all the way to Wugong (武县, in present-day Xianyang City, Shaanxi). By the 24th day of the eighth month of the lunar calendar, the sixteenth day of Emperor Taizong's ascension to the throne, the Turkic army had reached Gaoling (高陵, in present-day Xi'an, Shaanxi), which was not far from the Tang capital Chang'an.
Although Emperor Taizong of Tang sent Wei Chigong and others to lead the enemy and won a small victory at Jingyang (泾陽, in present-day Jingyang, Xianyang, Shaanxi), he was still unable to save the overall war and could not contain the pace of the Turkic invasion. In the end, the Turkic army still hit the Weishui River, which was only forty miles away from Chang'an City.
The Turkic army was stationed on the north bank of the Wei River, and for a time the people in Chang'an City were panicked. At this moment of a thousand guns, Tang Taizong Li Shimin decided to take the risk and take the sword to the side, and at the moment of the country's peril, Li Shimin took out his imperial mind and boldness. Therefore, the new emperor of the Tang Dynasty only brought Fang Xuanling, Gao Shilian and a few other retinues, and rode to the south bank of the Wei River.
[The Alliance of Weishui bought time for the prosperity of the Tang Dynasty, and the Tang Dynasty ushered in the first "Rule of Zhenguan"]
Li Shimin was a military genius, but also a master negotiator. He was not humble, fearless, and on the one hand, he rebuked Jieli Khan for reneging on his promise, and at the same time negotiated peace with him, and at the same time mobilized troops to come to his aid. In the end, under the suspicious tactics of Li Shimin, the Turks retreated out of fear, after which the Turks and the Tang Dynasty signed an armistice agreement on the Weishui Ben Bridge, the Weishui Alliance.
After signing the armistice, the two sides beheaded the white horse and formed an alliance, and then Jieli Khan withdrew from the Tang Dynasty with his Turkic army. Originally, a fierce battle under the soldiers in the city was strangled in the cradle under Li Shimin's "desperate risk".
The Alliance of Weishui made Li Shimin unforgettable, which was a test for him and a shame. However, it is undeniable that the Alliance of Weishui is also a great experiment of the victory of the weak over the strong, reflecting the strength and discernment of Li Shimin, the leader of the Tang Dynasty.
At that time, Li Shimin first ascended the throne, the troops in Chang'an City were empty, and the Turkic army came suddenly. The signing of the Weishui Alliance avoided a major war under extremely unfavorable circumstances for the Tang Dynasty, thus winning time for the Tang Dynasty to develop its economy and accumulate strength in the future.
After the Weishui Alliance, Tang Taizong exerted great efforts to develop the domestic economy on the one hand, and actively prepared for war on the other hand. Finally, in 630, the Eastern Turks were cleared from the historical stage, and Jieli Khan was captured, basically eliminating the Turkic threat to the Central Plains Dynasty.
In addition, the Tang Dynasty also calmed down many external troubles through a series of wars. During the Tang Dynasty, Emperor Taizong not only made great progress at home, but also made great achievements in foreign relations. After the elimination of the Eastern Turks, the Territory of the Tang Dynasty expanded to 600 miles north of the Yin Mountains, and its sphere of influence reached Lake Baikal. This was also the territory of the Central Plains Dynasty, the first and only time it reached the shores of Lake Baikal.
The Tang Dynasty was the pinnacle of agricultural society in Chinese history, and the rule of Zhenguan was an unforgettable rule. In the five thousand years of China, the interpretation of division and integration is full of a sentence: Backwardness will be beaten!
Only when the rulers are strong and discerning can the people have the opportunity to live and work in peace and contentment, the people can live and work in peace and contentment, the country can progress and be strong, and the country will not be bullied if it is strong.