Two of the members of ABBA, Agnetha Fältskog and Björn Ulvaeus, gave birth to a daughter named Linda in 1973. Around the same time, they also signed a deal with a baby food company, Semper. Linda eventually followed in her parents' footsteps and became a singer-songwriter herself. 

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Of course, it was the '70s so flamboyant outfits at the disco were only to be expected. But did you know that part of the reason ABBA chose their ostentatious outfits was because of a Swedish law that ensured performative outfits were tax-deductible? So long as clothes were used for performance, and not for daily wear, the Swedish government allowed artists to reduce their taxes. 

Yes, Madonna, the Madonna had famously been quoted saying she had to "beg" and "implore" ABBA to sample their music. She used the song Gimme, Gimme, Gimme (A Man After Midnight) on her single Hung Up. 

ABBA is famous for being incredibly protective of their music and very rarely give anyone rights to sample their songs. In an interview with Attitude magazine, Madonna was quoted saying: "I had to send my emissary to Stockholm with a letter and the record begging them and imploring them and telling them how much I worship their music, telling them it was a homage to them, which is all true." 

ABBA has only given rights to two artistes: Madonna and The Fugees. 

During the Cold War in the '70s, ABBA became immensely popular around the world. In fact, they were considered to be Sweden's top export, second only to the car manufacturer, Volvo. Even in Soviet states, ABBA found a large following. However, the ruble was then embargoed and so could not be used as payment for royalties. So instead, ABBA received its royalties through oil commodities. 

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