Most of the areas which today are within modern Greece's borders were at some point in the past a part of the Ottoman Empire.

This period of Ottoman rule in Greece, lasting from the mid-fiteenth century until the successful Greek War of Independence that breaks out in 1821 and the establishment of the modern Greek state in 1832, is known in Greek as Tourkokratia ("Turkish rule"; English: "Turkocracy").

Some regions, however, like the Ionian islands or Mani in the Peloponese are never part of the Ottoman administration, although the latter is under Ottoman suzerainty.The Byzantine Empire, the remnant of the ancient Roman Empire that had ruled most of the Greek-speaking world for over eleven hundred years, had been fatally weakened since the sacking of Constantinople by the Latin Crusaders in 1204.The Ottoman advance into Greece had been preceded by victory over the Serbs to its north.

First the Ottomans won the Battle of Maritsa in 1371.

The Serb forces were then led by the King Vukasin Mrnjavcevic, the father of Prince Marko and the co-ruler of the last emperor from the Serbian Nemanjic dynasty.

This was followed by another Ottoman victory in the 1389 Battle of Kosovo.With no further threat by the Serbs and the subsequent Byzantine civil wars, the Ottomans capture Constantinople in 1453 and advance southwards into Greece, capturing Athens in 1458.

The Greeks hold out in the Peloponnese until 1460, and the Venetians and Genoese cling to some of the islands, but by 1500 most of the plains and islands of Greece are in Ottoman hands.

The mountains of Greece are largely untouched, and are a refuge for Greeks to flee foreign rule and engage in guerrilla warfare.

Cyprus falls in 1571, and the Venetians retain Crete until 1669.

The Ionian Islands are only briefly ruled by the Ottomans (Kefalonia from 1479 to 1481 and from 1485 to 1500), and remain primarily under the rule of the Republic of Venice.Ottoman Greece is a multiethnic society as apart from Greeks and Turks there are many Jews, Italians (especially Venetians), Armenians, and various Balkan peoples (Serbs, Albanians, Roma (Gypsies), Bulgarians etc.)

However, the modern Western notion of multiculturalism, although at first glance appears to correspond to the system of millets, is considered to be incompatible with the Ottoman system.

The Greeks on the one hand are given some privileges and freedom; on the other they are exposed to a tyranny deriving from the malpractices of its administrative personnel over which the central government has only remote and incomplete control.

Despite losing their political independence, the Greeks remain dominant in the fields of commerce and business.

The consolidation of Ottoman power in the fifteenth and sixteenth centuries render the Mediterranean safe for Greek shipping, and Greek shipowners become the maritime carriers of the Empire, making tremendous profits.

After the Ottoman defeat at the Battle of Lepanto, however, Greek ships often become the target of vicious attacks by Catholic (especially Spanish and Maltese) pirates.

This period of Ottoman rule has a profound impact in Greek society, as new elites emerge.

The Greek landowning aristocracy that had traditionally dominated the Byzantine Empire suffers a tragic fate, and is almost completely destroyed.

The new leading class in Ottoman Greece are the prokritoi, called kocabaşis by the Ottomans.

The prokritoi are essentially bureaucrats and tax collectors, and gain a negative reputation for corruption and nepotism.

On the other hand, the Phanariots become prominent in the imperial capital of Constantinople as businessmen and diplomats, and the Greek Orthodox Church and the Ecumenical Patriarch rise to great power under the Sultan's protection, gaining religious control over the entire Orthodox population of the Empire, Greek and Slavic.