The oldest churches in Greece, the more significant being those in Thessaloniki, Nea Anchialos, Nikopolis, Athens and Corinth, date back to the Early Byzantine Period (4th - 6th Century A.D.).
During this period, important Ancient Greek temples, such as the Parthenon, the Erechtheion or the “Thission” in Athens, were converted into and functioned as churches, while many Christian churches were built near to or on the sites of known idolatry centers (e,g. Daphni, Elefsina, Delphi, Epidavros, Delos). Churches were also built on sites relating to persons or events that were important to Christians, such as the burial sites of martyrs.
Greek churches acquired an intensely local character during the Middle Byzantine Period (7th C. - 1204 A.D.) and were quite different from corresponding monuments in Constantinople. The more notable ones are situated in Attica, Viotia, Argolida, Mani, etc. Some of these are the katholicons or main churches of the monasteries they belong to.
The churches of the Late Byzantine Period (1204-1453) continue to follow traditional architectural models. Some of the most significant churches built during that period have been preserved in Arta, Veroia, Kastoria, Thessaloniki and Mystras Churches constructed after this period in regions under Frankish or Venetian occupation adopted quite a few western elements – architectural or decorative.
Churches built in Greece during the Ottoman occupation are especially austere. Exceptions to this were churches situated in areas under Venetian or generally Western influence (Crete, Ionian Islands). After the War of Independence, the economic recession did not allow the construction of ostentatious churches. An exception to this rule is the Metropolis of Athens, built in the middle of the 19th C. in order to function as the cathedral church in the capital of the newly-established Greek State. However, there was a new rise in ecclesiastical architecture from the end of the 19th C. and especially during the beginning of the 20th C.