What year did the Beatles broke up as band in?

A slightly complicated answer; effectively Lennon broke the band up in 1969, they decided to do one more "good" album - which was Abbey Road, all four Beatles were in the studio together for the last time in August 1969, although more Beatle recording and overdubs took place into early 1970. In 1970 Paul announced the break up publicly. Legally, the band separated in 1972. During the anthology project, the (then) three surviving Beatles worked on some Lennon demo tracks and released them as The Beatles - all three also acknowledged that they would be Beatles forever.