Socialism in New Zealand had little traction in early colonial New Zealand but developed as a political movement around the beginning of the 20th century. Much of socialism's early growth was found in the labour movement.

The politics of New Zealand function within a framework of an independent, unitary, parliamentary democracy. The system of government is based on the Westminster system, and the legal system is modelled on the common law of England. New Zealand is a constitutional monarchy in which King Charles III is the sovereign and head of state, while his prime minister serves as the head of government.