The contemporary use of the term is said to have appeared on the Internet in the late 1980s, but the earliest known attestation according to the Oxford English Dictionary is in 1992.

Where does trolling originate from?

[From the Usenet group alt. folklore. urban] To utter a posting on Usenet designed to attract predictable responses or flames. Derives from the phrase "trolling for newbies" which in turn comes from mainstream "trolling", a style of fishing in which one trails bait through a likely spot hoping for a bite.

Why do you call someone a troll?

A troll is Internet slang for a person who intentionally tries to instigate conflict, hostility, or arguments in an online social community. ... Trolls often use inflammatory messages to provoke emotional responses out of people, disrupting otherwise civil discussion.