Great Wallachia

Great Wallachia or Great Vlachia (Greek: Μεγάλη Βλαχία, Megáli Vlachía) or simply Vlachia (Βλαχία) was a province in southeastern Thessaly in the late 12th century, and was used to denote the entire region of Thessaly in the 13th and 14th centuries. The name derives from the Vlachs (Aromanians), who had lived across much of the area.

The name derives from the Aromanians or Vlachs, a chiefly transhumant ethnic group that lives in several mountainous areas of the Balkans, descended from ancient Romance-speaking populations mixed with the people from the Barbarian Invasions of Late Antiquity. In the broadest sense, both Greek and Western sources of the later Middle Ages—like the French, Italian, and Aragonese versions of the Chronicle of the Morea, or the chroniclers Ramon Muntaner and Marino Sanudo Torsello—used "Vlachia" or similar names (Blaquie, Blaquia, Val[l]achia) to refer to all of Thessaly, from the Pindus mountains in the west to the Aegean Sea in the east, and from the area of Mount Olympus and Servia in the north to the towns of Zetouni (Lamia) and Neopatras (Ypati) in the south.

Thessalian Vlachia was apparently also known as "Vlachia in Hellas" (ἐν Ἑλλάδι Βλαχία), as well as "Great Vlachia" (Μεγάλη Βλαχία), to distinguish it from other Vlach-inhabited areas, "Upper Vlachia" in Epirus, and a "Little Vlachia" in Aetolia-Acarnania. The contemporary Byzantine historian Niketas Choniates however distinguishes "Great Vlachia" as a district near Meteora. "Vlachia", "Great Vlachia", and the other variants began to fall out of use for Thessaly at the turn of the 14th century, and with the emergence of Wallachia north of the Danube, from the 15th century the name was reserved for it.

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