Monaco was represented by French singer Séverine, with the song '"Un banc, un arbre, une rue", at the 1971 Eurovision Song Contest, which took place on 3 April in Dublin. The song was chosen internally by broadcaster TMC and went on to bring Monaco their only Eurovision victory.

Following the contest "Un banc, un arbre, une rue" became one of the most commercially successful Eurovision winners to date. Séverine recorded versions of the song in several languages, although unusually it was the original French recording which reached number 9 on the UK Singles Chart rather than the English version ("Chance In Time"), which remained largely unknown. In later years Séverine would often claim that she had never been to Monaco prior to the contest, and would note wryly that neither had she been invited by TMC to visit the principality following her victory.

On the night of the final Séverine performed third in the running order, following Malta and preceding Switzerland. "Un banc, un arbre, une rue" was a cleverly structured song with four male backing singers repeating the melody of the chorus while Séverine sang the verses. Prior to the contest it had been rated by most observers as a particularly strong, memorable song, and the one to beat.

A new voting system was introduced for the 1971 contest, with two jury members from each country appearing on screen to award between 1 and 5 points to each song other than that of their own nation. The voters were split into six groups and after the third group had voted Italy held a narrow lead over Spain, with Monaco a little further back. However "Un banc, un arbre, une rue" then scored exceptionally strongly from the last three groups and emerged a clear winner with 128 points, 12 points ahead of runners-up Spain.

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Wikipedia