Guitarist/songwriter Björn Ulvaeus was half of the production duo that included fellow Swede Benny Andersson and produced the huge hits by '70s supergroup ABBA, best known for the number one pop single "Dancing Queen." Björn Christian Ulvaeus was born on April 25, 1945, in Gothenburg and began his performing career in a folk group. Producer Stig Anderson (who would later co-write "Dancing Queen") discovered them in 1963 and they moved to Stockholm. Anderson dubbed them the Hootenanny Singers and signed him to his label, Polar Records. Ulvaeus' song "Baby Those Are the Rules" was a Swedish Top Ten hit. He met Andersson, who had hits as a member of the Hep Stars, at a party, and the two decided to form a writing and producing team. Andersson met Anni-Frid Lyngstad in Malmo, Sweden, where they both were separately performing in nightclubs. Meanwhile, Ulvaeus met singer Agnetha Faltskog when they both appeared on a television show. The couples were married for a time. When Stig Anderson hired Ulvaeus and Andersson as staff producers for Polar, the two men began using their wives as background vocalists on recording sessions. With the recording of one of the duo's songs, "People Need Love," the two women took over the lead vocals. "People Need Love" was issued in America as being by the group Björn & Benny and Svenska & Flicka. After entering the Eurovision Song Contest, one of the quartet songs, "Waterloo," won first prize and became an international hit, due in part to the contest being televised all over the world. "Waterloo" was issued in the U.S. by Atlantic Records went to number six pop on Billboard's chart in summer 1974. Stig Anderson was tired of saying four names when he referred to the group, so he took the first letter of the group members' name and rearranged them into the name ABBA. "Waterloo"'s follow-up, "Honey, Honey, Honey," went to number 27 pop in fall 1974. ABBA's next charting singles, all on Atlantic, were "SOS," "I Do, I Do, I Do, I Do, I Do," "Mamma Mia," and "Fernando," which hit number one adult contemporary in fall 1976. But it wasn't until the shimmering million-selling "Dancing Queen" that ABBA had their first number one pop single in late 1976. Included on the gold LP Arrival, "Dancing Queen" was a massive disco hit. The hits continued: "Knowing Me Knowing You," "Money, Money, Money," "The Name of the Game," the gold "Take a Chance on Me" (number three pop), and "Does Your Mother Know." Besides The Arrival, other charting ABBA albums were the platinum LP The Album ("Take a Chance on Me"), the gold Voulez-Vous, the gold Super Trouper, and The Visitors. After ABBA split in 1982, Ulvaeus and Andersson collaborated with lyricist Tim Rice on the acclaimed hit Broadway musical Chess. Framed around the story of a Cold War-era chess match and love triangle between an American and a Russian master, the musical was a massive success, both critically and commercially. It spawned a hit album and several Tony Award nominations. The musical also featured singer Murray Head's version of the song "One Night in Bangkok," which reached number one in the U.K. and number three in the U.S. The pair also supplied many of the songs for Josefin Nilsson's 1993 album Shapes. Two years later, they premiered their long-gestating second musical production, Kristina Från Duvemåla, an epic Swedish-language musical based on author Vilhelm Moberg's The Emigrants novels. Also during the '90s, Ulvaeus and Andersson developed the hit musical Mamma Mia! Written by British playwright Catherine Johnson and based on the songs of ABBA, Mamma Mia! opened in 1999 on London's West End and was an immediate success. The musical ran for over a decade in London and on Broadway, and helped reignite interest in ABBA. In 2008, Meryl Streep starred in a popular film version of the musical. In 2013, Ulvaeus and Andersson paired with writer Kristina Lugn for the musical theater production Hjälp Sökes. ~ Ed Hogan, Rovi