Magna Graecia (, ; Latin meaning "Great Greece", Greek: Μεγάλη Ἑλλάς, Megálē Hellás, Italian: Magna Grecia) was the name given by the Romans to the coastal areas of Southern Italy in the present-day regions of Campania, Apulia, Basilicata, Calabria and Sicily; these regions were extensively populated by Greek settlers, particularly the Achaean settlements of Croton, and Sybaris, and to the north, the settlements of Cumae and Neapolis. The settlers who began arriving in the 8th century BC brought with them their Hellenic civilization, which was to leave a lasting imprint on Italy, such as in the culture of ancient Rome. Most notably the Roman poet Ovid referred to the south of Italy as Magna Graecia in his poem Fasti.
In the 8th and 7th centuries BC, because of demographic crises (famine, overcrowding, etc.), stasis (political crisis), the search for new commercial outlets and ports, and expulsion from their homeland after wars, Greeks began to settle in southern Italy. Colonies were established all over the Mediterranean and Black Seas (with the exception of Northwestern Africa, in the sphere of influence of Carthage), including in Sicily and the southern part of the Italian Peninsula. The Romans called the area of Sicily and the foot of Italy Magna Graecia (Latin for "Great Greece") since it was so densely inhabited by the Greeks. The ancient geographers differed on whether the term included Sicily or merely Apulia and Calabria, Strabo being the most prominent advocate of the wider definitions.
With colonization, Greek culture was exported to Italy, in its dialects of the Ancient Greek language, its religious rites and its traditions of the independent polis. An original Hellenic civilization soon developed, later interacting with the native Italic civilisations. The most important cultural transplant was the Chalcidean/Cumaean variety of the Greek alphabet, which was adopted by the Etruscans; the Old Italic alphabet subsequently evolved into the Latin alphabet, which became the most widely used alphabet in the world.
These Hellenic colonies became very rich and powerful, and some still stand today, like Neapolis ("New City", now Naples), Syracuse, Akragas (Agrigento), Taras (Taranto), Rhegion (Reggio Calabria), or Kroton (Crotone).
The first Greek city to be absorbed into the Roman Republic was Neapolis in 327 BC. The other Greek cities in Italy followed during the Samnite Wars and the Pyrrhic War; Taras was the last to fall in 272. Sicily was conquered by Rome during the First Punic War. Only Syracuse remained independent until 212, because its king Hiero II was a devoted ally of the Romans. His grandson Hieronymous however made an alliance with Hannibal, which prompted the Romans to besiege the city, which fell in 212, despite the machines of Archimedes.
During the Early Middle Ages, following the disastrous Gothic War, new waves of Byzantine Christian Greeks may have come to Southern Italy from Greece and Asia Minor, as Southern Italy remained loosely governed by the Eastern Roman Empire. Although possible, the archaeological evidence shows no trace of new arrivals of Greek peoples, only a division between barbarian newcomers, and Greco-Roman locals. The iconoclast emperor Leo III appropriated lands that had been granted to the Papacy in southern Italy and the Eastern Roman (Byzantine) Empire continued to govern the area in the form of the Catapanate of Italy through the Middle Ages, well after northern Italy fell to the Lombards.
At the time of the Normans' late medieval conquest of southern Italy and Sicily (in the late 12th century), the Salento peninsula (the "heel" of Italy) and up to one third of Sicily was still Greek speaking (concentrated in the Val Demone). At this time the language had evolved into medieval Greek, also known as Byzantine Greek, and its speakers were known as Byzantine Greeks. The resultant fusion of local Byzantine Greek culture with Norman and Arab culture (from the Arab occupation of Sicily) gave rise to Norman-Arab-Byzantine culture on Sicily.
A remnant of this influence can be found in the survival of the Greek language in some villages of the above mentioned Salento peninsula (the "heel" of Italy). This living dialact of Greek, known locally as Griko, is found in the Italian regions of Calabria and Apulia. Griko is considered by linguistics to be a descendant of Byzantine Greek, which had been the majority language of Salento through the Middle Ages, combining also some ancient Doric and modern Italian elements. There is a rich oral tradition and Griko folklore, limited now but once numerous, to around 30,000 people, most of them having become absorbed into the surrounding Italian element. Some scholars, such as Gerhard Rohlfs, argue that the origins of Griko may ultimately be traced to the colonies of Magna Graecia.
Although many of the Greek inhabitants of Southern Italy were entirely Latinized during the Middle Ages (for example, Paestum was by the 4th century BC), pockets of Greek culture and language remained and survived into modernity partly because of continuous migration between southern Italy and the Greek mainland. One example is the Griko people, some of whom still maintain their Greek language and customs.
Greeks re-entered the region in the 16th and 17th century in reaction to the conquest of the Peloponnese by the Ottoman Empire. Especially after the end of the Siege of Coron (1534), large numbers of Greeks took refuge in the areas of Calabria, Salento and Sicily. Greeks from Coroni, the so-called Coronians, were nobles, who brought with them substantial movable property. They were granted special privileges and tax exemptions.
Other Greeks who moved to Italy came from the Mani Peninsula of the Peloponnese. The Maniots were known for their proud military traditions and for their bloody vendettas, many of which still continue today. Another group of Maniot Greeks moved to Corsica.