The man hailed by George Orwell as the nation's true folk artist, and whose work symbolises the kiss-me-quick seafronts where his cards were sold, lies under an unkempt piece of grass in Streatham Park cemetery in plot no 30508. Only a small piece of numbered wood marks the spot.
Yesterday, McGill fans and leading commentators queued up to condemn the neglect of arguably the most popular artist of the past 100 years. The film director Michael Winner, who has 200 of McGill's original works, said: "It's terrible. Terrible. He was the Thomas Rowlandson of his day. It's beyond belief that he died and then went into an unmarked grave." Winner even offered to pay for a headstone himself: "I would certainly pay to have that nicely done and put in properly. I will do that as a mark of respect."
Professor Robin Procter, McGill's grandson, said: "I am surprised and saddened that he is buried in an unmarked grave. My family was abroad in South Africa at the time. He was a fantastic chap."
Dr Nick Hiley, head of cartoon studies at the University of Kent, said: "I am surprised and puzzled McGill is buried in an unmarked grave. He deserves a memorial."
In life, Donald McGill was a bookish but twinkle-eyed man who lived all his life in the London suburbs of Blackheath and Streatham, and who resembled, in his quiet, dapper way, nothing so much as a small-town solicitor. He was not wealthy, was paid only a fee for each postcard, received no royalty for their stupendous sales, and, in his will, left only £735.
But between 1904 and his death in 1962, he dreamt up and drew an estimated 10,000 original cards, which became, as Orwell put it, a potent form of folk art. They sold in their scores of millions, not least because they evoked a music-hall world inhabited by McGill's own repertory company of comic stereotypes: henpecked husbands, jolly fat ladies, red-nosed boozers, thin-lipped clergymen, blousy barmaids, desperate spinsters, lascivious milkmen and tight-fisted Scots.
But in July 1954, McGill, then nearly 80, was hauled before Lincoln Quarter Sessions to face charges under the Obscene Publications Act. The offending items included: flighty girl to bookmaker at racecourse: "I want to back the favourite, please. My sweetheart gave me a pound to do it both ways"; and a cheery seaside chappy holding an outsize stick of seaside rock on his knees with the caption "A stick of rock, cock?". Advised to plead guilty, McGill did so on six counts, and was fined £50 with costs. Thus did the English law, not a lifetime ago, deem that six seaside postcards of undisguised jolliness would deprave and corrupt the population so much that they warranted burning.
Michael Winner said: "The charge of obscenity against him was beyond comprehension, even for the 1950s.There's no hint of obscenity in any of his stuff."
'Censored at the Seaside - The Postcards of Donald McGill' is on BBC4 on 22 October at 9.10pm