March of Styria

The March of Styria (German: Steiermark), originally known as Carantanian march (Karantanische Mark, marchia Carantana after the former Slavic principality of Carantania), was a southeastern frontier march of the Holy Roman Empire. It was broken off the larger March of Carinthia, itself a march of the Duchy of Bavaria, around 970 as a buffer zone against the Hungarian invasions. Under the overlordship of the Carinthian dukes from 976 onwards, the territory evolved to be called Styria, so named for the town of Steyr, then the residence of the Otakar margraves. It became an Imperial State in its own right, when the Otakars were elevated to Dukes of Styria in 1180.

After the Slavic settlement of the Eastern Alps from about 590 and the establishment of the Carantanian principality in the 7th century, the area had fallen under Bavarian suzerainty, when about 740 Prince Boruth asked Duke Odilo for help against invading Avar forces. Incorporated into the Carolingian Empire by Charlemagne, Frankish manoralism was introduced and the northwestern areas were resettled by Bavarian peasants. The population was Christianized by the Archbishops of Salzburg. However, large parts of former Carantania were again lost during the invasion of Hungarian troops culminating in the East Frankish defeat in the 907 Battle of Pressburg.

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