March of Pannonia

The Eastern March (Latin: marcha orientalis) or March of Pannonia was a frontier march of the Carolingian Empire, named after the former Roman province of Pannonia. It was erected in the mid-ninth century in the lands of the former Avar Khaganate against the threat of Great Moravia and lasted only as long as the strength of that state. It was referred to in some documents as terminum regni Baioariorum in Oriente or "the end of the kingdom of the Bavarians in the east" and from this is sometimes called the "(Bavarian) eastern march," a term more commonly used to refer to the later Margraviate of Austria, established in 976 as a sort of late successor state. The East Frankish rulers appointed margraves (prefects) to govern the March.

Charlemagne, temporarily allied with Khan Krum of Bulgaria, from 791 onwards had launched several military camapaigns against the Avars and had established the Avar March (Avaria) on the southeastern frontier of his realm, ruled by his brother-in-law Prefect Gerold of Bavaria. When the Avar Khaganate finally collapsed in 804, Emperor Charlemagne re-arranged Avaria into:

The eastern part of the former Khaganate between the Danube and Tisza Rivers was occupied by the Bulgars.

In 817 Emperor Louis the Pious granted Bavaria with Avaria to his minor son Louis the German. When the Avars disappeared in the 820s, they were replaced largely by West Slavs, who settled Pannonia from the state of Great Moravia. From 819 Lower Pannonia was the site of a rebellion led by Duke Ljudevit Posavski against the rule of Duke Cadolah of Friuli and his successor Baldric.

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