The first known use of ‘fuck’ appears in a set of medieval case files for a man called Roger Fuckbythenavele. He was in court 3 times before being outlawed in 1311, and the repeated formal use of his last name suggests it wasn’t meant to be a joke- however, it may have been a nick- name he earned for being known as a virgin or a moron, as it implies he was either too naive or too dumb to know you can’t have sex through the belly button. Source Source 2