His great-great-grandfather Kang Ruji (康汝楫) served the Yongle Emperor in his household and was appointed a vice minister in his government in 1403.
There that he interacted with influential persons, earning friends and some enemies for his outspoken opposition to corruption and his literary style.
In 1508 when the powerful eunuch Liu Jin was manipulating the young Zhengde Emperor, Kang Hai joined forces with other scholars in opposing him.
[1] For the next thirty years, Kang "acted the part of a non-conformist hermit" with his friend Wang Jiusi, fearing being called back to office.
[1] The friends loved to drink wine, play the pipa, be noisy and act "like fools in order to give expression to their grievances".