It is not known when or where Wang Kai was born. It is known that he served as an emissary of Emperor Zhaozong of Tang during the Tianfu era to Xichuan Circuit late in Tang Dynasty, and thereafter remained in Xichuan, which was then ruled by Wang Jian.
During Former Shu
After Tang Dynasty fell in 907 and Wang Jian declared himself emperor of a new Shu state over his domain, Wang Kai became an imperial scholar. He later became the deputy chief imperial censor. In 909, Wang Jian made him Zhongshu Shilang, the deputy head of the legislative bureau of government, and gave him the designation Tong Zhongshu Menxia Pingzhangshi, making him a chancellor. In 911, when Wang Jian built a new palace and issued an edict ordering the collection of books, Wang Kai submitted a petition praising the effort and outlining how many emperors in history have used various efforts to collect and encouraged the reading of books. In 912, Wang Kai was removed from his chancellor position and made the minister of defense, but in 913 was restored to the chancellor and Zhongshu Shilang positions. During the subsequent reign of Wang Jian's son Wang Zongyan, Wang Kai served as chancellor with Yu Chuansu. At that time, Wang Yan's associates Han Zhao and Pan Zaiying led Wang Yan to spend much of his time in frivolous activities, and it was said that Wang Kai, Yu, and most other officials did little to try to change Wang Yan's ways. Indeed, even after a very expensive trip that Wang Yan took to Lang Prefecture, after which many officials did submit petitions urging against such trips in the future, Wang Kai said nothing and did not resign in protest. When a major invasion from Later Tang led to Wang Yan's surrender and Former Shu's fall in 925, Wang Yan had the imperial scholar Li Hao draft the surrender petition and Wang Kai draft the surrender letter.
After Former Shu
Emperor Zhuangzong initially promised Wang Yan that he would be created an honorable title, and Li Jijisubsequently sent Wang Yan and a large group of Former Shu officials on their way to the Later Tang capital Luoyang in 926. However, after the Later Tang realm began to be embroiled in a large number of rebellions, Emperor Zhuangzong initially ordered Wang Yan to halt at Chang'an, and then put him and his family to death. The Former Shu officials, by order, continued to proceed to Luoyang, but by the time they reached Luoyang, Emperor Zhuangzong himself had been killed in a mutiny at Luoyang and succeeded by his adoptive brother Emperor Mingzong. Emperor Mingzong commissioned many former Former Shu officials to be regional officials, and Wang Kai was made a prefectural prefect. Wang Kai and a number of former Former Shu officials subsequently submitted a petition urging for the proper burial of Wang Yan's body, and for this they were praised by people. The rest of Wang Kai's career, and his death date, are not known. However, it is known that Wang Kai had a large collection of rare booksat home, and that he himself had written lengthy commentaries. He was also well known for his calligraphy and studiousness.
