March of Carinthia

The March of Carinthia was a frontier district (march) of the Carolingian Empire created in 889. Before it was a march, it had been a principality or duchy ruled by native-born Slavic (or semi-Slavic) princes at first independently and then under Bavarian and subsequently Frankish suzerainty. The realm was divided into counties which, after the succession of the Carinthian duke to the East Frankish throne, were united in the hands of a single authority as a march of defence against the Slavs of Pannonian Croatia. When the march of Carinthia was raised into a Duchy in 976, a new Carinthian march (that is, a march defending the Carinthian duchy) was created. It became the later March of Styria.

In 745, Carantania, an independent Slavic principality, with the growth of the Avar threat, submitted to Odilo of Bavaria, himself a vassal of the Franks. With this, the Bavarian frontier was extended and Odilo's son, Tassilo III, began the Christianisation of the Slavic tribes beyond the Enns. In 788, Charlemagne fully integrated the territory of Carinthia (Carantania) into the Frankish Empire by making it a part of the extended Duchy of Friuli, along with the March of Istria. Under him, missionary work increased, especially through the Archdiocese of Salzburg.

Between 819 and 823, the native Slavic population supported Ljudevit Posavski in revolt against Frankish overlordship. In 827, the Bulgars attacked Carinthia and, in 828, Louis the Pious reorganised Friuli into four counties, the two northernmost of which — Carinthia and Lower Pannonia — were detached from the Italian kingdom and incorporated into Bavaria. Louis, King of Bavaria, reorganised Carinthia into Frankish counties soon after. The division of Carinthia may have occurred as early as before 819 or perhaps simultaneously with division of Friuli. Before this, the Carinthians were still ruled by native dukes. The new comital administration was mixed Bavarian-Slavic.

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