The breakup of the Beatles was a devastating moment in music history. Although the band had previously experienced upheaval with Ringo Starr and George Harrison quitting and then returning, the 1970 breakup was the end of an era (via Metro). Paul McCartney revealed who was responsible for the Beatles' split, saying that it was John Lennon who initially declared his intentions to leave the group. McCartney quoted Lennon as saying it was "quite thrilling" and "rather like a divorce" when he announced his decision. Beatles legend had often placed McCartney at fault for initiating the breakup, but it was, in fact, Lennon who wanted them to go their separate ways (per The Guardian).
Source: Heather Baver/thelist.com