The relationship changes were reflected in the group's music, with latter compositions featuring darker and more introspective lyrics. With the increase of their popularity, their personal lives suffered, which eventually resulted in the collapse of both marriages. During the band's main active years, it consisted of two married couples: Fältskog and Ulvaeus, and Lyngstad and Andersson. In 1974, ABBA were Sweden's first winner of the Eurovision Song Contest with the song ' Waterloo', which in 2005 was chosen as the best song in the competition's history as part of the 50th anniversary celebration of the contest. One of the most popular and successful musical groups of all time, they became one of the best-selling music acts in the history of popular music, topping the charts worldwide from 1974 to 1983, and in 2021. The group's name is an acronym of the first letters of their first names arranged as a palindrome. ABBA ( / ˈ æ b ə/ AB-ə, Swedish:, formerly named Björn & Benny, Agnetha & Frida) are a Swedish pop group formed in Stockholm in 1972 by Agnetha Fältskog, Björn Ulvaeus, Benny Andersson, and Anni-Frid Lyngstad.
