Siw Gunnel Margareta Malmkvist (born 31 December 1936) is a Swedish schlager singer and actress popular in Scandinavia and West Germany (today's Germany). She represented Sweden in the Eurovision Song Contest 1960 and West Germany in the Eurovision Song Contest 1969.
She had a number one hit in West Germany in 1964 with "" ("Lovesickness Is Not Worthwhile"), and on 18 July 1964 she became the first Swede to have a hit on the US Billboard Hot 100 chart, when "", a duet with Italian singer , entered the chart, peaking at No. 58. Malmkvist is notable for having recorded in more than 10 languages, including Swedish, English, Finnish, Norwegian, Danish, Dutch, French, Italian, Spanish and particularly German.
Siw Malmkvist grew up in Landskrona as one of nine siblings. She is the daughter of Albert Malmkvist (1901âÂÂ1979) and Sigrid Lind (1899âÂÂ1988), as well as the older sister of singer Lil Malmkvist and aunt to Morgan Alling.
Her career started when she participated in orchestras in SkÃÂ¥ne. In 1955 she participated in a singing competition, which defined her career. She won the first round of competition locally in SkÃÂ¥ne, and got to travel to Stockholm Concert Hall, where the grand final took place. She won the final, receiving a clock as an award, and recorded her first grammophone record, called Tweedle Dee. Malmkvist had also worked as an invoice clerk in Landskrona.
Her breakthrough came in 1959 when she was a hostess on Lennart Hyland's television show . The same year, she won Melodifestivalen with the song "Augustin", but did not get to represent Sweden in Eurovision Song Contest, as Brita Borg was internally selected to sing the song in Cannes. With the song "Augustin", Malmkvist got her first hit song. It went on to place fourth on Show-Business magazine's bestseller list on 1 March 1959, and sold over 60,000 copies. One year later, Malmkvist would represen Sweden in the Eurovision Song Contest 1960 in London with the song "Alla andra fÃÂ¥r varann", where she ended up placing tenth. In the Swedish Melodifestivalen the same year, Inger Berggren and ÃÂsten Warnerbring had won with the same song song, but Malmkvist had been internally selected for Eurovision. Malmkvist again won Melodifestivalen in 1961, with the song "April, April", but again, SVT internally selected another singer to perform it in Eurovision, this time Lill-Babs.
In 1959, she launched her career in West Germany, where she became very popular. In 1961, she had a hit song with the song "". In 1960, she released the song "Die Liebe ist ein seltsames Spiel" under the pseudonym "Die Jolly Sisters". Later, she would release the song in Sweden as well with the title "", which became a hit, topping the chart for seven weeks and selling over 97,000 copies. Her next song, "", sold over 80,000 copies. From 1963 onward, she lived in Helsinki, Finland, with her husband Lasse MÃÂ¥rtenson and their daughter. During this time in 1964, she became the first Swedish singer to place on the Billboard hit list. Along with Umberto Marcato, she sang the song "" in Italian and peaked at number 58 for five weeks.
Malmkvist had success in the singing competition Schlager-Festspiele in Baden-Baden. At the debut in 1962, she placed second with "". In 1964, she won the competition with "", which sold 1,000,000 copies and peaked at number one on the West Germany chart for ten weeks, In Swedish, the song was named "". In 1968, she won the competition once again with the song "". In 1969, she won the West German selection for the Eurovision Song Contest the same year with the song "Primaballerina", placing seventh in Madrid. To this day, Malmkvist's songs remain popular in Germany. In Melodifestivalen 1988, she participated with the song "".
Malmkvist had an acting career in Denmark as well as Sweden. Amongst other roles she played the leading role in the film (1960) and as Eivor in Varning för Jönssonligan (1981). She soon also showed talent on stage; she had the leading role in the musical Irma la douce. She also participated in the at Folkan in 1972, and in the Karl Gerhard show at Vasateatern. In 1980, she played the role of Pippi Longstocking in a play at Folkan in Stockholm. She received acclaim for her role as Luise in the musical Nine at Oscarsteatern 1983âÂÂ84, where she acted against Ernst-Hugo JäregÃÂ¥rd. In later years, Malmkvist has acted in the musical at Nöjesteatern in Malmö. In 2008, she played Fräulein Schneide in Colin Nutley's version of the musical Cabaret at Stockholms stadsteater.
In later years she has done many shows, including on Hamburger Börs in Stockholm, along with Lill-Babs and Wenche Myhre. She participated in Melodifestivalen 2004 with the song "C'est la vie" along with Towa Carson and Ann-Louise Hanson. The trio went on to sing at AllsÃÂ¥ng pÃÂ¥ Skansen, which is broadcast on SVT. Between 2003 and 2012, Malmkvist participated in the Arlövs revue show every year. In 2003 and 2004, she took part in the Diggiloo summer tour. On 2 June 2004, Malmkvist, along with Wenche Myhre and Gitte Henning, debuted their show , in Germany, Austria and Switzerland. The tour continued until June 2008 in Kiel, with a total of 350 shows. Together with actor Thorsten Flinck, she recorded a Swedish cover of Nick Cave/Kylie Minogue's 1995 hit "Where the Wild Roses Grow", called "". In 2005, Malmkvist participated in the TV4 show Körslaget, where she was eliminated first on 5 April.
In 2009, she was a celebrity guest on SVT1's Stjärnorna pÃÂ¥ slottet, where she discussed her life and career. Between 2010 and 2011, Malmkvist, along with Lill-Babs and Ann-Louise Hanson, had a show called . In 2010, Malmkvist published her memoirs, named .
In 2011, she performed at AllsÃÂ¥ng pÃÂ¥ Skansen performing a medley of her hits. In 2012, she participated on the SVT show , the Swedish version of Who Do You Think You Are?. On the show, she was told her ancestors were soldiers at the Battle at Poltava and that she had Snapphanar amongst her relatives.
Malmkvist signed on to be a celebrity dancer on Let's Dance 2020, which is broadcast on TV4. However, on 17 March it was revealed that she would not participate because of restrictions concerning the COVID-19 virus.
In 2021, she took part in two episodes of the TV4 show SÃÂ¥ mycket bättre.
In 2023, Malmkvist was a guest celebrity judge on the episode "MARATHON Talent Hunt" of the Swedish-language reality television series Drag Race Sverige broadcast on SVT1 and SVT Play.
In 2025, the documentary film () premiered in Swedish cinemas. In December of that year, SVT broadcast a three-part documentary series on Malmkvist's life and career, called Siw.
On 24 December 2025, Malmkvist was the (), the presenter for SVT's Christmas Eve broadcasts.
Malmkvist was married to Finnish-Swedish musician Lasse MÃÂ¥rtenson from 1963 to 1969, and the couple have one daughter. Malmkvist was in a relationship with actor Fredrik Ohlsson from 1971 until his death in 2023; the couple have a son together born in 1973.