What is the name of ABBA's first number one hit in the UK?

ABBA’s first number-one hit in the UK was “Waterloo.”

Released in 1974, “Waterloo” gave ABBA its breakthrough on the British singles chart. The song became a UK number-one single and was the first of the group’s nine UK number-one singles. Its success followed ABBA’s victory at the Eurovision Song Contest in Brighton, England, where the group performed the song in April 1974.

“Waterloo” combines upbeat pop with elements of glam rock, schlager, and early rock and roll. The title uses Napoleon Bonaparte’s defeat at the 1815 Battle of Waterloo as a metaphor for surrendering to love. ABBA’s colorful costumes and energetic performance also helped make the song memorable to television audiences across Europe.

A frequent mix-up is “Dancing Queen,” which is often considered ABBA’s signature song and later became the group’s first US number-one single. “Mamma Mia” and “Super Trouper” were also major UK hits, but neither was ABBA’s first British chart-topper.