Duchy of Lower Pannonia

Lower Pannonia (Latin: Pannonia inferior) was an entity located in the southwestern parts of the former Roman province of Pannonia, held by Slavic rulers between the fall of the Avar Khaganate starting in the 790s, and the Hungarian conquest of the Carpathian Basin in the 890s. The Slavic counts were predominantly under Frankish suzerainty, part of Frankish Pannonia, and are known from Frankish primary sources. In the mid-9th century, Lower Pannonia was inhabited by a Slavic majority.

During the reign of Justinian I (527–565), in the mid-6th century, the Avars that stayed in Dobrudja had demanded Byzantine territory, but refused the offer of Lower Pannonia. After Justin II discontinued the tribute to the Avars, they marched on Eastern Frankish territory.

The Royal Frankish Annals makes mention of a Wonomyrus Sclavus (Vojnomir the Slav) active in 795.Eric, Duke of Friuli, sent Vojnomir with his army into Pannonia, between the Danube and Tisza, where they pillaged the Avars' dominions. The next year the Avars were defeated and Frankish power was extended further east, to the central Danube.

Initially, the Slavic counts were under Frankish suzerainty, part of Frankish Pannonia (the Pannonian March), and are known from Frankish primary sources.

Ljudevit was mentioned in the Frankish Annals as Liudewitus, dux Pannoniae inferioris, having led an uprising against the Franks, joined by the Carantanians and other Slavic tribes.

In 827, the Bulgars under Great Khan Omurtag invaded and conquered Lower Pannonia and parts of Frankish territories to the north. In 829 the Bulgars imposed a local Slavic prince, Ratimir, as the new ruler of Pannonia. His province is believed to have been the territory of Roman Pannonia Savia. In 838, nine years later, following the Bulgar conquest of Macedonia, the Danubian count Radbod, prefect of the East March, deposed Ratimir and restored Frankish rule in Pannonia. Ratimir fled the land, and the Franks next instated Slavic princes Pribina and Kocel as rulers of Pannonia.

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