Jireček Line

The Jireček Line is a conceptual boundary through the ancient Balkans that divides the influence of the Latin (in the north) and Greek (in the south) languages in the Roman Empire from Antiquity until the 4th century. It goes from near the city of Laçi in modern Albania to Serdica (now Sofia, in Bulgaria) and then follows the Balkan Mountains to Odessus (Varna) on the Black Sea. However, the proposed line is a theoretical tool only, and a few groups of latinized people live south of the line: Aromanians, Meglenites, Cutzovlachs (Βλαχοι), Moscopolitans, etc. Nonetheless, it is a correct, if somewhat rough, instrument in determining to whether influence a certain area was predominantly exposed. The placing of the line is based on archaeological findings: most of the inscriptions found to the north of it were written in Latin, and most of the inscriptions found to the south of it were in Greek.

This line is important in establishing the area that the Romanian and Vlach people formed (see origin of the Romanians).

It was originally used by Czech historian Konstantin Jireček in 1911 in a history of the Slavic people.

More recent scholars have revised it somewhat: Kaimio (1979) places Dalmatia and Moesia Superior in the Latin area and Moesia Inferior in the Greek sphere. MacLeod (1982) suggests that there may not have been "an official language policy for each and every aspect of life" but that "individual Roman officials [made] common sense ad hoc decisions". He also points out that during that time, when the area was under the Roman rule, "even in Greek areas... Latin was the dominant language in inscriptions recording public works, on milestones, and in the army".

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