April 6 1974: It’s 50 years since an obscure Swedish band wearing all the satin Scandinavia had available won the kitsch-fest that is the Eurovision Song Contest. Abba’s winning song was Waterloo, named after the 1815 battle. But it became an upbeat contemplation of a woman surrendering herself to an insistent suitor. Genius! And a bit wrong. Because, of course, Napoleon didn’t surrender at Waterloo, but at Rochefort.

In 1973, Abba had failed to qualify for Eurovision with Ring Ring. But with Waterloo’s tune, the twin vocals of Agnetha Fältskog and Anni-Frid Lyngstad, and the lyrics by band manager Stig Anderson, the track soon went from song-quest winner to enduring earworm.

Only Anderson was allowed on stage to accept the award despite Benny Andersson and Björn Ulvaeus being the composers. Officials held back the pair by their platform boots as they climbed the stage steps. Recalled Ulvaeus: “The guard said, ‘You’re not a writer, you’ve misunderstood this, you dumb Swede! You have to wait.’ The way I was dressed, he would have thought, ‘He can’t be the writer.’”