Why were all the descendants of Yu Wenyu in the Northern Zhou Dynasty killed by Emperor Wen of Sui Dynasty?

Yu Wenyu specially wrote a poem for Wei Xun in order to express his respect for him. Yu Wenyu wrote: "Six hexagrams of divination avoid the world, and the sun, the moon and the stars are less bright. Angelababy pushed ancient times, and Cangzhou is gone forever. The aroma comes from the swaying Qiu Lan ornaments, and the clothes made of lotus leaves flutter in the breeze. " This poem is relatively long, and Yu Wenyu expressed his admiration and respect for Wei Xun in it. Yu Wenyu fantasizes that one day he can travel around the great rivers and mountains of the motherland with Duan Wei and other celebrities, sit on a big stone by the stream and spy out the fairy cave, and chat and fish by the stream on a small raft.

Knowing Yu Wenyu's life, Yu Wenyu has four children. Yu Wenxian, the king of Bila, Yu Wenzhen, Jia Wang, Wang Song Yu and Princess Henan are all children of Yu Wenyu. The history books do not record the life story of Yuwen Yu's daughter in detail, except that Bila Wang Yuxian is the eldest son of Yuwen Yu, Jia Wang Yuwen is the second son of Yuwen Yu, and Wang Song Yuwen Shi is the third son of Yuwen Yu. Princess Henan is the only daughter of Yu Wenyu. Baoding four years, Yu Wenxian was named Bi Guogong.

In the third year of Jiande, Yu Wenxian was promoted to king. In the Northern Zhou Dynasty, Yu Wenxian served as the secretariat of Huazhou and Jingzhou successively. The ruler recognized Yu Wenxian very much and made him a pillar of talent. Yu Wenxian is very capable and a talented official. Before his death, let Yu Wenxian assist Yu in handling state affairs. At that time, Emperor Wendi of Sui Dynasty was worried that Yu Wenxian would destroy his plan to proclaim himself emperor, so he was wary of Yu Wenxian everywhere. Emperor Wen of Sui Dynasty abandoned Yu, became emperor on his own, and changed his country name to Sui, so he wanted to get rid of Yu Wenxian. Worried that Yu Wenxian and his descendants would restore the Northern Zhou regime, Emperor Wendi of Sui Dynasty tried his best to execute Yu Wenxian, killing Yu Wenxian's son Yu Hongyi and Yu Gongzheng.

Yuwen Zhen is the second son of Yuwen Yu, and the history books do not record who Yuwen Zhen's biological mother is. Yu Wenzhen was first named the king of the country. In 574 AD, Yu Wenzhen became the King of Huan. In 579 AD, Yu Wenzhen ascended the throne of Otsuka. After Emperor Wendi established the Sui regime, he killed Yu Wenzhen and his descendants. So Yu Wenyu's third son. Like his two brothers, Emperor Wendi of Sui Dynasty was worried that his descendants would revolt in the future and overthrow the regime of Sui Dynasty. In order to ensure the stability of the foundation of the Sui Dynasty, Emperor Wendi of Sui Dynasty also executed Yu.