Tsakonia or the Tsakonian region (Greek Τσακωνιά or Τσακωνικός χώρος) describes the area of the eastern Peloponnese where the Tsakonian language is presently spoken. It is not a formally defined political entity of the modern Greek state, being more akin to such vague regional constructions as "Dixie" in the United States or "West Country" in England.
In his Brief Grammar of the Tsakonian Dialect published in 1951, Prof. Thanasis Costakis defines Tsakonia as the area from the town of Agios Andreas in Kynouria south to Leonidio and Tyros and inland as far as Kastanitsa and Sitaina, but asserts that in former times the Tsakonian-speaking area extended as far as Cape Malea in eastern Laconia. The principal town in Tsakonia at this time was Prastos, which benefitted from a special trading privilege granted by the authorities in Constantinople. Prastos was burned by Ibrahim Pasha in the Greek War of Independence and was abandoned, with many of its residents fleeing to the area around Leonidio and Tyros or other spots on the Argolic Gulf.
Some early commentators seem to have confused the speech of Maniot dialect speakers with true Tsakonian, demonstrating the flexible nature of the term.
The actual Tsakonian speech community has shrunk greatly since Brief Grammar's publication, but the area delineated by Costakis is still considered "Tsakonia" due to the preservation of certain cultural traits such as the Tsakonian dance and unique folk costumes.