Greeks or Hellenes (; Greek: Έλληνες, Éllines [ˈelines]) are an ethnic group and nation native to Greece, Cyprus, southern Albania, Turkey, southern Italy, parts of Egypt, and to a lesser extent, other countries surrounding the Eastern Mediterranean and Black Sea. They also form a significant diaspora (omogenia) around the world.
Greek communities have been historically established on the shores of the Mediterranean Sea and the Black Sea, but the Greek people themselves have always been concentrated on the Aegean Sea and the Ionian Sea, where the Greek language has been spoken since the Bronze Age. Until the early 20th century, Greeks were distributed between the Greek peninsula, the western coast of Anatolia as well as Cappadocia, the Black Sea coast, Egypt, the Balkans, Cyprus, and Constantinople. Many of these regions coincided to a large extent with the borders of the Byzantine Empire of the late 11th century and the Eastern Mediterranean areas of ancient Greek colonization. The cultural centres of the Greeks have included Athens, Thessalonica, Alexandria, Smyrna, and Constantinople at various periods.
In more recent history, most ethnic Greeks have lived within the borders of the modern Greek state or in Cyprus, as the Greek genocide and subsequent Greek–Turkish population exchange nearly ended the three-millennia-old Greek presence across Asia Minor. Other longstanding Greek populations can be found from southern Italy to the Caucasus, southern Russia and Ukraine, and in the Greek diaspora communities in a number of other countries, especially in the Western world. Today, most religious Greeks are Christians officially registered with the Greek Orthodox Church.
The Greek people have greatly influenced and contributed to culture, visual arts, exploration, theatre, literature, philosophy, ethics, politics, architecture, music, mathematics, medicine, science, technology, commerce, cuisine, and sports. The Greek language, which constitutes an independent branch within the Indo-European language family, is the oldest recorded living language, and its vocabulary has been the basis of many languages (including English) and the international scientific nomenclature. As early as the 4th century BC, the Greek language spread to become the most widely spoken lingua franca in the Mediterranean world for over a millennium, earning effective co-official status in the Roman Empire and also being the language in which the New Testament of the Christian Bible was originally written.