At the turn of the 20th century, the radical side of New Zealand working class politics was represented by the Socialist Party, founded in 1901. The more moderate leftists generally supported the Liberal Party. In 1905 a group of working-class politicians who were dissatisfied with the Liberal approach established the Independent Political Labour League (IPLL), which managed to win a seat in Parliament in the . At the same time, moderates contested as "Lib-Lab" candidates, aligning with the Liberal Party while enjoying the endorsement of the labour movement. This established the basic dividing line in New Zealand's left-wing politics – the Socialists/IPLL tended to be revolutionary and militant, while the moderates focused instead on progressive reform. The process of unifying these sides into a single party was difficult, with tensions between different factions running strong.
At the turn of the 20th century, the radical side of New Zealand working class politics was represented by the Socialist Party, founded in 1901. The more moderate leftists generally supported the Liberal Party. In 1905 a group of working-class politicians who were dissatisfied with the Liberal approach established the Independent Political Labour League (IPLL), which managed to win a seat in Parliament in the  At the same time, moderates contested as "Lib-Lab" candidates, aligning with the Liberal Party while enjoying the endorsement of the labour movement. This established the basic dividing line in New Zealand's left-wing politics – the Socialists/IPLL tended to be revolutionary and militant, while the moderates focused instead on progressive reform. The process of unifying these sides into a single party was difficult, with tensions between different factions running strong.