Short answers, pulled from the story.
John, Paul, George, Ringo ... and Bert premiered at the Everyman Theatre in Liverpool in May 1974. It ran there for eight weeks before transferring to the Lyric Theatre in London in August 1974, where it ran for a year.
Willy Russell wrote the musical in 1974. It was directed by Alan Dossor and was based on the story of the Beatles.
The musical was named Best Musical of 1974 by both the Evening Standard Theatre Awards and the London Critics' awards.
George Harrison attended the London premiere with Derek Taylor and greatly disliked it, according to an interview he gave to Creem magazine. He subsequently withdrew permission to use his song "Here Comes the Sun", which was replaced in the production with "Good Day Sunshine".
Paul McCartney blocked the proposed film adaptation because he criticised the musical for being biased against him and in favour of John Lennon. He objected specifically to the suggestion that he, rather than Lennon, was responsible for the break-up of the Beatles.
Bernard Hill played John Lennon, Trevor Eve played Paul McCartney, Phillip Joseph played George Harrison, and Anthony Sher played Ringo Starr. George Costigan played Bert, the narrator figure whose name appears in the title.