From the perspective of ordinary people's families, Li Yuan is 3 years older than Yang Guang, yang Guang wants to call Li Yuan a "cousin", and the mothers of both are the daughters of DuGuxin. However, in the context of history, one is the king of the fallen country, the other is the founding king, and the relationship between the two is extremely complicated. And it is worth mentioning that both have been treated unfairly by history, and their merits and abilities have been significantly weakened.
Homology:
Wuchuan, a land of bullets, but gathered enough wang qi, the ancestors of the Zhou, Sui, and Tang dynasties all came from this place, and here formed a warlord of Wuchuan Town. During the Western Wei Dynasty, Yuwen Tai initiated the military system of fu, with the twelve generals and the Eight Pillar State as generals, these generals were from Wuchuan, they went out and entered the phase, and intermarried with each other, which was the later Guanlong clique. Among them, Yang Guang's grandfather Yang Zhong was one of the twelve generals, Li Yuan's grandfather Li Hu was one of the Eight Pillar States, and DuGuxin was also one of the Eight Pillar States. The Yang family and the Li family are both important members of the Guanlong Group.
Cousin Relationships:
Li Xun, the Duke of Tang, married Dugu Xin's fourth daughter, Empress Yuanzhen of the Dugu clan, and in 566 gave birth to a son Li Yuan, Yang Jian married Du Gu Xin's seventh daughter, Empress Du Lonely Jialuo, and in 569 gave birth to a son Yang Guang. The cousins were supposed to be friendly when they were young, Li Yuan died when his father died when he was seven years old, he inherited the Duke of Tang, and Yang Guang was given the title of Duke of Yanmen County because of his father's relationship.
In 581, the relationship between the two underwent a major change, Yang Jian usurped the Zhou title of emperor, the Sui Dynasty was established, his son Yang Yong was made crown prince, Yang Guang was made the King of Jin, the official Baizhu Guo, and the governor of the prefecture, after which various positions were added, and in 600 he replaced Yang Yong as crown prince. Li Yuan was given the title of Qianniu Bei at the beginning of Yang Jian's claim to the throne, and Li Yuan became the military attaché of the Sui Wen Emperor Yang Jian, and because of his kinship, Li Yuan was heavily respected by Yang Jian, and successively made the history of the three prefectures of Qi, Qi, and Long.
Monarch-subject relationship:
In 603, Yang Guang was proclaimed emperor, and Li Yuan served as the Taishou of Xingyang and Lou Fu, and was later appointed as the Young Inspector of the Palace and the Young Secretary of Wei Wei. In 613, Yang Xuan felt anti-Sui, Li Yuan was ordered to guard the town of Honghua, and a rift appeared in the trust between the monarchs and subjects, Li Yuan was hospitable, and he was jealous of Yang Guang, and then there were uprisings everywhere, and Li Yuan was ordered to suppress the uprising while inviting rebellion and expanding his power. In 617, Li Yuan served as a defender of Taiyuan, where he had the strength to raise an army and raise the banner of rebellion against The Sui.
Relationship between the usurper and the old lord:
In July 617, Li Yuan officially raised an army with 30,000 troops, and in November he attacked Chang'an, and Li Yuan honored Yang Guang, who was trapped in Jiangdu, as emperor, and installed Yang Guang's grandson Yang You as emperor, while Li Yuan became the King of Tang, the Grand Chancellor, and Shang Shu Ling, and controlled the imperial government. The following year, Yang Guang was killed at Jiangdu, Yang You stepped down, and Li Yuan officially declared himself emperor and established the Tang Dynasty.
In fact, throughout the lives of Yang Guang and Li Yuan, the two have many relationships, such as
Nephew-uncle relationship:
Li Yuan's sister had a queen clan with Princess An Chang, and entered the palace to become Yang Guang's concubine, from this level, Yang Guang wanted to call his cousin Li Yuan an uncle, but Yang Guang was a jun, Li Yuan was a subject, this layer of relationship is only in mutual co-optation, can not really take out the title, and Wang clan is only a concubine, that is, a concubine, this layer of relationship weakened a lot.
Also weakened was the relationship between the children and the family: Li Yuan's son Li Shimin had adopted Yang Guang's daughter Yang Shi as a concubine, giving birth to Li Ke the King of Wu and Li Yan the King of Shu. Even weaker was the fact that Li Yuan had accepted several of Yang Guang's concubines.
In fact, in the big picture, the relationship between Yang Guang and Li Yuan is nothing more than the relationship between cousins before the establishment of the Sui Dynasty, the relationship between the monarch and the subject after Yang Guang succeeded to the throne, and the relationship between the old lord and the new king in the change of dynasties.
In fact, no matter what kind of family relationship, once it is related to power, it becomes no longer simple and less important, not to say that it is a cousin, even if it is a brother of a mother and a compatriot, in the face of power, the same you and I live, such as Li Shimin and Li Jiancheng in the change of Xuanwumen.