Greece is an orthodox country with over 96% referring themself as Christian Greek Orthodox.
Greek was the English of modern times back then it was spoken to travel like latin the official language of the Roman empire.
Greek Orthodoxy church foundation can be traced back to Jesus time. However Jesus never spoke in Greek.
Jesus spoke Hebrew and Syriac languages.
Most churches in Greece are Greek Orthodox.
The islands of Syros and Tinos in the Cyclades have still a Roman-Catholic-Latin presence of local people that can be traced back all the way of the Venetian Republic.
In the following greek islands there are catholic churches but mostly used by tourist and overseas workers. Naxos, Santorini, Crete, Rhodes, Kos, Chios, Corfù.
In Athens there is the catholic cathedral and in Thessaloniki there is another big catholic church.
In the island of Syros, Orthodox and Catholic celebrate at the same date Holy Easter (orthodox date).
Franciscan friars can be found in Rhodes island in the Dodecanese.
Protestant and evangelical have a small presence in Greece.
In the picture the statue of Our Lady of Fatima in the Catholic church in Mykonos island.
Lean more about the 150 Angelic Salutation prayer tradition in the Christian Orthodox Church. A devotion from the VIII century requested from the Mother of God to the people.