Google Ngram Viewer shows that “fuck” used to be a lot more common in books during the 1700s and has only recently started to make a comeback. The reason for this is that there used to be common usage of the long s (ſ) in place of a normal s at the start or middle of words. One result of this is “suck” appearing to be “fuck” to Google’s character recognition software.
As a reddit commenter posts, this can be seen even more clearly when viewing suck, fuck, suckle, and fuckle plotted together. Notice that fuck takes the place of suck and fuckle the place of suckle, despite fuckle not even being a word.