Most of Greece was part of the Ottoman Empire from the 14th century until its declaration of independence in 1821. The Ottoman Turks first crossed into Europe in 1354.
The Byzantine Empire, which had ruled most of the Greek-speaking world for over 1100 years, had been fatally weakened since the sacking of Constantinople by the Crusaders in 1204.
Ottoman advance into Greece was preceded by victory over the Serbs to its north. First the Ottomans won at 1371 on the Maritsa River - where the Serb foces were led by the King Vukasin Mrnjavcevic, the father of Marko Kraljevic and the co-ruler of the last emperor from the Serbian Nemanjic Kynasty. This was followed by another Ottoman victory in the 1389 Battle of Kosovo.
With no further threat by the Serbs, the Ottomans could advance southwards into Greece, capturing Athens in 1458. The Greeks held out in the Peloponnese until 1460, and the Venetians and Genoese clung to some of the islands, but by 1500 most of the plains and islands of Greece were in Ottoman hands. The mountains of Greece were largely untouched, and were a refuge for Greeks to flee foreign rule.
Cyprus fell in 1571, and the Venetians retained Crete until 1670. The Ionian Islands were only briefly ruled by the Ottomans (Kefalonia from 1479 to 1481 and from 1485 to 1500), and remained primarily under the rule of Venice.
The consolidation of Ottoman rule was followed by two distinct trends of Greek migration. The first entailed Greek intellectuals, such as Johannes Vissarion, Georgius Plethon Gemistos and Marcos Mousouros, migrating to Western Europe and influencing the advent of the Renaissance (though the large scale migration of Greeks to the West, most notably Italian University cities, began far earlier, following the Crusader capture of Constantinople).
The second entailed Greeks leaving the plains of the Greek peninsula and resettling in the mountains, where the rugged landscape made it hard for the Ottomans to establish either military or administrative presence.
The conquered land was parcelled out to Ottoman nobles, who held it as feudal fiefs (timars and ziamets) directly under the Sultan's authority. The land could not be sold or inherited, but was reverted to the Sultan's possession when the fief-holder died.
As a rule, the Ottomans did not require the Greeks to become Muslims, although many did so in order to avert the economic hardships of Ottoman rule. Under the millet logic, a converted Greek, although retaining culture and language, was classified simple as "Muslim". In the eyes of the Christians, however, they were deemed Turks. Some Greeks either became neo-martyrs, such as Saint Efraim the Neo-Martyr or Saint Demetrios the Neo-martyr while others became Crypto-Christians (Greek Muslims who were secret practitioners of the Greek Orthodox faith) in order to avoid heavy taxes and at the same time express their identity by maintaining their secret ties to the Greek Orthodox Church. Crypto-Christians ran the risk of being killed if they were caught practicing a non-Muslim religion once they converted to Islam.
The worst persecutions of Christians took place under the reign of Selim I, known as Selim the Grim, who attempted to stamp out Christianity from the Ottoman Empire. Selim ordered the confiscation of all Christian churches, and while this order was later rescinded, Christians were heavily persecuted during his era.
Greeks also paid a land tax and a tax on trade, but these were collected irregularly by the inefficient Ottoman administration. Provided they paid their taxes and gave no trouble, they were left to themselves. Greeks, like other Christians, were also made to pay the jizya, or Islamic poll-tax which all non-Muslims in the empire were forced to pay in order to practice their religion. Non-Muslims did not serve in the Sultan's army, but young boys were forcibly converted to Islam and made to serve in the Ottoman military.
These practices are called the "tribute of children" (devshirmeh) (in Greek παιδομάζωμα paidomazoma, meaning "child gathering"), whereby every Christian community was required to give one son in five to be raised as a Muslim and enrolled in the corps of Janissaries, elite units of the Ottoman army. This imposition, at first, aroused surprisingly little opposition since Greeks who were living on the plains could not offer effective resistance. Still, there was much passive resistance, for example Greek folklore tells of mothers crippling their sons to avoid their abduction. Nevertheless, entrance into the corps (accompanied by conversion to Islam) offered Greek boys the opportunity to advance as high as governor or even Grand Vizier.
Opposition of the Greek populace to taxing or paidomazoma resulted in grave consequences. For example, in 1705 an Ottoman official was sent from Naoussa in Macedonia to search and conscript new Janissaries and was killed by Greek rebels who resisted the burden of the devshirmeh. The rebels were subsequently beheaded and their severed heads were displayed in the city of Thessaloniki. The "tribute of children" was met with various reactions ranging from contempt to support. In some cases, it was greatly feared as Greek families would often have to relinquish their own sons who would convert and return later as their oppressors. In other cases, the families bribed the officers to ensure that their children got a better life as a government officer. The Greek historian Papparigopoulos stated that approximately one million Greeks were conscripted into Janissaries during the Ottoman era.
On the other hand, the position of educated and privileged Greeks within the Ottoman Empire improved in the 17th and 18th centuries. As the empire became more settled, and began to feel its increasing backwardness in relation to the European powers, it increasingly recruited Greeks who had the kind of administrative, technical and financial skills which the Ottomans lacked. From about 1700 Greeks began to fill some of the highest offices of the Ottoman state. The Phanariotes, a class of wealthy Greeks who lived in the Phanar district of Constantinople, became increasingly powerful. Their travels to Western Europe as merchants or diplomats brought them into contact with advanced ideas of liberalism and nationalism, and it was among the Phanariotes that the modern Greek nationalist movement was born. Many Greek merchants and travelers were influenced by the ideas of the French revolution and a new Age of Greek Enlightment was initiated at the beginning of 17th century in many Ottoman occupied Greek cities and towns.
Greek nationalism was also stimulated by agents of Catherine the Great, the Orthodox ruler of the Russian Empire, who hoped to acquire the lands of the declining Ottoman state, including Constantinople itself, by inciting a Christian rebellion against the Ottomans. However, during the Russian-Ottoman War which broke out in 1768, the Greeks did not rebel, disillusioning their Russian patrons. The Treaty of Kuchuk-Kainarji (1774) gave Russia the right to make "representations" to the Sultan in defence of his Orthodox subjects, and the Russians began to interfere regularly in the internal affairs of the Ottoman Empire. This, combined with the new ideas let loose by the French Revolution of 1789, began to reconnect the Greeks with the outside world and led to the development of an active nationalist movement.
Greece was only peripherally involved in the Napoleonic Wars, but one episode had important consequences. When the French under Napoleon Bonaparte seized Venice in 1797, they also acquired the Ionian Islands. The islands were elevated to the status of a French dependency called the Septinsular Republic, which possessed local autonomy. This was the first time Greeks had governed themselves since the fall of Constantinople in 1453. Among those who held office in the islands was John Capodistria, destined to become independent Greece's first head of state. By the end of the Napoleonic Wars in 1815, Greece had re-emerged from its centuries of isolation. British and French writers and artists began to visit the country, and wealthy Europeans began to collect Greek antiquities. These "philhellenes" were to play an important role in mobilizing support for Greek independence.
A secret Greek nationalist organization called the "Friendly Society" or "Company of Friends" (Filiki Eteria) was formed in Odessa in 1814. The members of the organization planned a rebellion with the support of wealthy Greek exile communities in Britain and the United States. They also gained support from sympathizers in Western Europe, as well as covert assistance from Russia. The organization secured Capodistria, who became Russian Foreign Minister after leaving the Ionian Islands, as the leader of the planned revolt. On March 25 (now Greek Independence Day) 1821, the Orthodox Bishop Germanos of Patras proclaimed a national uprising. Simultaneous risings were planned across Greece, including in Macedonia, Crete, and Cyprus. With the initial advantage of surprise, aided by Ottoman inefficiency and Turk's fight against Ali Pasha of Tepelen, the Greeks succeeded in capturing the Peloponnese and some other areas. Some of the first Greek actions were taken against unarmed Ottoman settlements, with about 40% of Turkish and Albanian Muslim residents of the Peloponnese killed outright, and the rest fleeing the area or being deported.
The Ottomans soon recovered, and retaliated in turn with similar savagery, massacring the Greek population of Chios and other towns. This worked to their disadvantage by provoking further sympathy for the Greeks in Western Europe, although the British and French governments suspected that the uprising was a Russian plot to seize Greece and possibly Constantinople from the Ottomans. The Greeks were unable to establish a coherent government in the areas they controlled, and soon fell to fighting amongst themselves. Inconclusive fighting between Greeks and Ottomans continued until 1825 when the Sultan sent a powerful fleet and army from Egypt to ravage the Aegean Islands and the Peloponnese.
The atrocities that accompanied this expedition, together with sympathy aroused by the death of the poet and leading philhellene Lord Byron at Messolongi in 1824, eventually led the Western Powers to intervene. In October 1827, the British, French and Russian fleets, on the initiative of local commanders but with the tacit approval of their governments destroyed the Ottoman fleet at the Battle of Navarino. This was the decisive moment in the war of independence. In October 1828, the French landed troops in the Peloponnese to stop the Ottoman atrocities. Under their protection, the Greeks were able to regroup and form a new government. They then advanced to seize as much territory as possible, including Athens and Thebes, before the Western Powers imposed a ceasefire.
A conference in London in March 1829 proposed an independent Greek state with a northern frontier running from Arta to Volos, and including only Euboia and the Cyclades among the islands. The Greeks were bitterly disappointed at these restricted frontiers, but were in no position to resist the will of Britain, France and Russia, who were largely responsible for Greek independence. By the Convention of May 11, 1832, Greece was finally recognized as a sovereign state. Capodistria, who had been Greece's unrecognized head of state since 1828, was assassinated in October 1831. To prevent further experiments in republican government, the Western Powers insisted that Greece be a monarchy, and the Bavarian Prince Otto, rather than someone with a Greek origin was chosen to be its first king.