March of Carinthia

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.

[3] With this, the Bavarian frontier was extended and Odilo's son, Tassilo III, began the Christianisation of the Slavic tribes beyond the Enns.

[4] 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.

In 855, Radbod, Prefect of the Ostmark was deposed for unfaithfulness and Rastislav of Moravia rebelled against East Frankish suzerainty.

Carloman took control of the other eastern marches, Carinthia and Pannonia, and in 858 campaigned heavily against Rastislav, forcing him to come to terms.

When Carloman reconciled with his father and was created King of Bavaria, he granted Carinthia to his son by a Carinthian concubine, Arnulf.

The only known Carinthian margrave from this period — though many counts are known — is Markward III, who was a preses de Carinthia.

He made Carinthia a duchy for the Liutpoldinger Henry, who acted as a sort of "chief of the border police," controlling Istria, Friuli, and Carniola.