Alþýðuflokkurinn Icelandic Political Party based on Social Democratic ideas, was founded in 1916 as the political field of the labour union of Iceland. Social democracy is a political ideology emerging in the late 19th and early 20th centuries from supporters of Marxism who believed that the transition to a socialist society could be achieved through democratic evolutionary rather than revolutionary means. ...

It´s first member of Althingi was Jón Baldvinsson elected in 1920.

Three times the party led the government of Iceland; in 1947-1949 under Stefán Jóhann Stefánsson, in 1958-1959 under Emil Jónsson and under Benedikt Gröndal in 1979-1980. Its longest participation in Government was with the Independence Party from 1959-1971. Stefán Jóhann Stefánsson was Prime Minister of Iceland from 4 February 1947 to 6 December 1949. ... Emil Jónsson was Prime Minister of Iceland from 23 December 1958 to 20 November 1959. ... Benedikt Sigurdsson Gröndal (born July 7, 1924) was Prime Minister of Iceland for the Social Democrats (Alþýðuflokkurinn) from 15 October 1979 to 8 February 1980. ... The Independence Party (Sjálfstæðisflokkurinn) is a center-right political party in Iceland. ...