The National Schism, also sometimes called The Great Division, was a series of disagreements between King Constantine I and Prime Minister Eleftherios Venizelos regarding the foreign policy of Greece in the period of 1910–1922 of which the tipping point was whether Greece should enter World War I. Venizelos was in support of the Allies and wanted Greece to join the war on their side, while the pro-German King wanted Greece to remain neutral, which would favor the plans of the Central Powers.

Eleftherios Kyriakou Venizelos was a Cretan Greek statesman and prominent leader of the Greek national liberation movement. He is noted for his contribution to the expansion of Greece and promotion of liberal-democratic policies. As leader of the Liberal Party, he held office as prime minister of Greece for over 12 years, spanning eight terms between 1910 and 1933. During his governance, Venizelos entered in diplomatic cooperation with the Great Powers and had profound influence on the internal and external affairs of Greece. He has therefore been labelled as "The Maker of Modern Greece" and is still widely known as the "Ethnarch".