Between the Wars
- Women allowed to stand for election to the House of Representatives, but not for appointment to the Legislative Council.
- National poll for prohibition (a ban on the production, sale and consumption of alcohol) narrowly defeated by the number of votes cast by troops serving overseas.
- Anzac Day instituted.
- Immigration Restriction Act passed, allowing officials to reject immigrants who did not have British birth or parentage, and supporting an unofficial 'White New Zealand' policy.
- Chatham Islands inhabitants able to vote.
- Election results broadcast for the first time on the radio.
- Compulsory registration on electoral roll required for all eligible non-Māori voters.
- Family Allowances Act passed.
- United Party formed from remnants of Liberal Party.
- Postal voting for elections introduced.
- New Government formed after general election by United Party, led by Sir Joseph Ward, supported by Labour and independent members.
- Sir Joseph Ward dies and is succeeded as leader of the United Party by George Forbes.
- Labour withdraws from coalition.
- Coalition of Reform and United parties led by George Forbes wins general election.
- Eruera Tirakaten elected as first Ratana MP.
- National Expenditure Adjustment Act passed, reducing pensions, State employees salaries, rents and other charges.
- Rioting in Auckland.
- Elizabeth McCombs first woman elected to Parliament in Lyttelton by-election.
- Legal age for marriage set at 16 years.
- Legislation passed to establish Reserve Bank.
- First Labour Government, with Michael Joseph Savage as Prime Minister.
- Ratana movement wins two Māori seats.
- National Party formed from Reform and United coalition MPs.
- Standard working week reduced from 44 to 40 hours for most workers.
- Labour and Ratana form alliance.
- Elections for Māori seats use secret ballot for first time.
- Beginnings of two-party politics in New Zealand, with Labour and National winning more than 96% of the votes cast.
- First use of radio for party political broadcasts.
- Social Security Act passed, revising pensions structure and establishing a national health service.
- Death of Michael Joseph Savage, succeeded as PM by Peter Fraser.
- Sidney Holland becomes Leader of the Opposition.
- Labour-Ratana alliance wins all four Māori seats, ousting Apirana Ngata after almost 40 years as the Eastern Māori MP.