"McCartney revisited – 2: After the ball" - This is an interesting summary of how the critical reaction to McCartney, Paul's first post-Beatles album, changed over the years. I didn't agree with all of it - especially the contention that Paul didn't feel he had much to prove once The Beatles disbanded - but I found it a worthwhile read overall.
It is difficult, and probably pointless, to resist the conclusion that the public perception of the McCartney album was coloured by resentment towards Paul for having supposedly broken up the Beatles. No doubt it was also influenced by an expectation – in the aftermath of the release of the highly polished and astonishingly good Abbey Road – that both John Lennon and Paul McCartney would individually produce records sounding like Beatle albums on which the other three members of the group happened not to be playing or writing any of the songs. Neither John Lennon/Plastic Ono Band nor McCartney, of course, was anything of the kind – which explains the adverse public reaction of the day to both records, despite what is now widely recognized as the monumental, albeit harrowing, brilliance of Lennon’s debut post-Beatles album.
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It is noteworthy how the critical assessment of Paul’s first post-Beatles album has tended to become more positive over time, as the initial gloom at news of the dissolution of the Beatles has dissipated, and resentment at McCartney for being the supposed agent of that dissolution has disappeared and therefore ceased to sway perceptions of the McCartney album. For all the critical sniping that went on at the time of its release, the album sold in very large quantities, reaching Number 2 on the UK album chart and peaking at Number 1 in America, where it topped the chart for three weeks in late May to early June 1970. (It was displaced from the Number 1 position in the US only by Let It Be, which became the last studio album of new songs ever to be released by the Beatles. Following an argument between Paul and the other three Beatles, the release date of Let It Be was put back in order not to clash with the release date of McCartney, after Paul refused to delay the previously agreed date of issue of his solo album so as to allow Let It Be to come out first.)