Complex sentence: Until around 820, it was ruled as a semi-independent tribal polity; after the anti-Frankish rebellion of Ljudevit Posavski, which was partially supported by Carantanians, the Carantanian principality was transformed into a Frankish march, and later emerged as the Feudal Duchy of Carinthia.
Split into simpler sentences: Until around 820, it was ruled as a semi-independent tribal polity. After the anti-Frankish rebellion of Ljudevit Posavski, which was partially supported by Carantanians, the Carantanian principality was transformed into a Frankish march, and later emerged as the feudal Duchy of Carinthia.