The Greek War of Independence, also known as the Greek Revolution (Greek: Ελληνική Επανάσταση, Elliniki Epanastasi; Ottoman: يونان عصياني Yunan İsyanı Greek Uprising), was a successful war of independence waged by the Greek revolutionaries between 1821 and 1832 against the Ottoman Empire. The Greeks were later assisted by the Russian Empire, Great Britain, the Kingdom of France, and several other European powers, while the Ottomans were aided by their vassals, the eyalets of Egypt, Algeria, and Tripolitania, and the Beylik of Tunis.
Even several decades before the fall of Constantinople to the Ottoman Empire in 1453, most of Greece had come under Ottoman rule. During this time, there were several revolt attempts by Greeks to gain independence from Ottoman control. In 1814, a secret organization called the Filiki Eteria was founded with the aim of liberating Greece. The Filiki Eteria planned to launch revolts in the Peloponnese, the Danubian Principalities, and in Constantinople and its surrounding areas. By late 1820, the insurrection had been planned for March 25 (Julian Calendar) 1821, on the Feast of the Annunciation for the Orthodox Christians. However, as the plans of Filiki Eteria had been discovered by the Ottoman authorities, the revolutionary action started earlier. The first of these revolts began on March 6/February 22, 1821 in the Danubian Principalities, but it was soon put down by the Ottomans. The events in the north urged the Greeks in the Peloponnese into action and on 17 March 1821, the Maniots declared war on the Ottomans. This declaration was the start of a spring of revolutionary actions from other controlled states against the Ottoman Empire.
On March 25 the revolution was officially declared and by the end of the month, the Peloponnese was in open revolt against the Turks. By October 1821, the Greeks under Theodoros Kolokotronis had captured Tripolitsa. The Peloponnesian revolt was quickly followed by revolts in Crete, Macedonia, and Central Greece, which would soon be suppressed. Meanwhile, the makeshift Greek navy was achieving success against the Ottoman navy in the Aegean Sea and prevented Ottoman reinforcements from arriving by sea.