The Balkan campaign of the First World War (also known as the Salonika or the Macedonian campaign) came about because of the changing strategic aims of the Allies and Central Powers and the complex politics of the region. New Zealand’s role in the campaign was limited but directly affected by these issues. 

Central to the story of New Zealand and the Balkans was the Greek island of Lemnos, of strategic importance to the Gallipoli Campaign and command of the Eastern Mediterranean. However, the presence of British, Australian and New Zealand troops on Greek territory posed an acute diplomatic problem. In 1915, Greece was officially neutral but bitterly divided between two factions supporting the opposing sides. King Constantine I had German ancestry and was married to the Kaiser’s sister; his sympathies for Germany and Austro-Hungary were clear. On the other side, Prime Minister Eleutherios Venizelos favoured the Allies. Greece had not fulfilled its treaty obligations to come to Serbia's aid when the Austro-Hungarians declared war on Serbia in July 1914, and both Greek society and the military were split over the adoption of neutrality as the nation's official response to the war. Venizelos eventually established a rival government in northern Greece in October 1916, but the struggle was not resolved until June 1917, when Constantine was deposed in favour of his son Alexander and Greece officially joined the Allies.

Greek neutrality, not withstanding, the Gallipoli invasion fleet assembled at Lemnos in April 1915. Despite the opposition of King Constantine to this development, Venizelos's faction blocked any attempt by the Greek government to actively oppose the Allied occupation of the island. Troops practised disembarkation and rowing the boats which would carry them to the beaches. A few men went ashore and explored the villages. Many would return during the Gallipoli campaign; in September 1915, most of the exhausted New Zealand contingent on the Gallipoli Peninsula was withdrawn to Lemnos for a rest, only returning to action in November 1915. Others were evacuated to the island during the fighting, either wounded or suffering from diseases such as dysentery.

Life on the island was pleasant compared to the hardships of Gallipoli – the September rest period for the New Zealand forces at Sarpi Camp on Mudros Bay was particularly welcome:

Here at least there was no shelling, and the food, in quality and quantity, surpassed our most sanguine expectations. For the first time on active service we tasted the luxury of [army] canteens. Even recreational institutes sprang up. Day by day the men gained strength until they were colourable [sic] imitations of the original arrivals at Anzac.

Fred Waite, The New Zealanders at Gallipoli, 2nd edn, 1921, pp. 261–2

Following the evacuation of Anzac Cove, completed on 20 December 1915, most of the New Zealand troops returned briefly to Lemnos to await the voyage back to Egypt and further training and campaigning.