The military history of New Zealand during World War I began in August 1914. When Britain declared war on Germany at the start of the First World War, the New Zealand government followed without hesitation, despite its geographic isolation and small population. It was believed at the time that any declaration of war by the United Kingdom automatically included New Zealand; and the Governor (the Earl of Liverpool) announced that New Zealand was at war with Germany from the steps of Parliament on 5 August.
The total number of New Zealand troops and nurses to serve overseas in 1914–18, excluding those in British and other Dominion forces, was 100,444, from a population of just over a million. Forty-two percent of men of military age served in the New Zealand Expeditionary Force, fighting in the Gallipoli campaign and on the Western Front. 16,697 New Zealanders were killed and 41,317 were wounded during the war – a 58 percent casualty rate. Approximately a further thousand men died within five years of the war's end, as a result of injuries sustained, and 507 died while training in New Zealand between 1914 and 1918.
The First World War saw Māori soldiers serve for the first time in a major conflict with the New Zealand Army (although a number had fought in the Second Boer War when New Zealand recruiters chose to ignore British military policy of the time of disallowing 'native' soldiers). A contingent took part in the Gallipoli campaign, and later served with distinction on the Western Front as part of the New Zealand (Māori) Pioneer Battalion. 2,227 Māori and 500 Pasifika, including 150 Niueans, served with New Zealand forces in total.
Outbreak of the war
On 30 July 1914, the British Admiralty informed Captain Herbert Marshall, the senior naval officer in New Zealand, by telegram that a war in Europe was likely. This followed the declaration of war made by Austria-Hungary against Serbia, the news of which threatened to bring Russia, and her allies, Britain and France, into the conflict. A War Council, which included Marshall, Prime Minister William Massey, and Major General Alexander Godley, the commandant of the New Zealand Military Forces, was formed. This authorised the commencement of certain mobilisation and defensive procedures. These included implementing inspections of incoming vessels at the four major ports, mobilisation of the garrison artillery to man the various forts around the country, and commencement of censorship. Radio stations and the sites where undersea telegraph cables came on shore were placed under guard. The cruiser HMS Philomel, on a training cruise in the Cook Strait was recalled and made ready for war, such as it could be given its rundown state. The country's small Royal Naval Reserve was called up on 2 August to help crew the cruiser.
The conflict in Europe escalated in the following days when Germany declared war on Russia and then on 4 August invaded Belgium. This brought France and Britain into the war in support of Belgium. The outbreak of World War I was announced in the afternoon of 5 August by the Governor of New Zealand, Lord Liverpool, when he read out aloud the telegram dispatched by the Colonial Office confirming the commencement of hostilities to a crowd of 15,000 people gathered outside the old Parliament Building in Wellington. Although a self-governing Dominion, such were New Zealand's ties to Great Britain as part of the British Empire it was inherently understood that the country was automatically at war as well. Massey, speaking to the crowd after Lord Liverpool's proclamation of war, urged his fellow citizens to "keep cool, stand fast, do your duty to your country and your Empire".
There was bi-partisan support in Parliament for its position in standing alongside Great Britain and its Dominions; both Massey's Reform government and its Liberal opposition made strong expressions of support. The leader of the Liberal Party, Joseph Ward, made it clear that the British Empire could not be uninvolved in any fighting against the Central Powers. The general population, at least 20% of whom were born in Great Britain, also demonstrated keen patriotism and an appreciation that New Zealand needed to play a role in the ensuing conflict. As the news of the war spread, crowds gathered at central points in major cities and marched and cheered in support of Britain and her allies. However, the indigenous people of New Zealand, the Māori, had a more muted reaction; not having the same links to Great Britain, they were only a small proportion of the population and were not a part of mainstream society.