In the seventh century the area was part of the Slavic principality of Carantania, which fell under the suzerainty of Duke Odilo of Bavaria in about 743. The Bavarian stem duchy was incorporated into the Carolingian Empire when Charlemagne deposed Odilo's son Duke Tassilo III in 788. In the 843 partition by the Treaty of Verdun, Carinthia became part of East Francia under King Louis the German. From 889 to 976 it was the Carinthian March of the renewed Bavarian duchy, though in 927 the local Count Berthold of the Luitpolding dynasty was vested with ducal rights by the German king Henry the Fowler. After Berthold became Duke of Bavaria in 938, both territories were ruled by him. Upon his death in 948 the Luitpoldings, though heirs of the royal Ottonian dynasty, were not able to retain their possessions, as King Otto I bought the loyalty of his younger brother Henry I with the Bavarian lands.
Establishment
Duke Henry's son Henry II "the Quarreller" from 974 onwards, revolted against his cousin Emperor Otto II, whereupon he was deposed as Duke of Bavaria in favour of Otto's nephew Duke Otto I of Swabia. At the same time Emperor Otto II created a sixth duchy in addition to the original stem duchies, the new Duchy of Carinthia. He reverted the possession of the territories to the Luitpoldings, when he split Carinthia from the Bavarian lands and installed the former Duke Berthold's son Henry the Younger as duke in 976.
Over the centuries, the name 'Carinthia' (Kärnten) gradually replaced former 'Carantania'. The realm of the Carinthian dukes initially comprised a vast territory including the marches of Styria (marchia Carantana), Carniola and Istria; they also ruled over the Italian March of Verona in the south. Nevertheless, Henry the Younger was the first and also the last Luitpolding duke; as he chose to join the unsuccessful War of the Three Henries against Emperor Otto II, he lost Carinthia two years later and was succeeded by the Emperor's nephew Otto I, a scion of the Salian dynasty. Though Henry once again managed to regain the ducal title in 985, Carinthia upon his death in 989 fell back to the Imperial Ottonian dynasty in Bavaria.
Eppensteins and Sponheims
Carinthia, however, remained a separate entity, and in 1012 Count Adalbero I of Eppenstein, Margrave of the Carinthian March (later Styria) since about 1000, was vested with the duchy by the last Ottonian emperor Henry II, while the Istrian march was separated and given to Count Poppo of Weimar. Adalbero was removed from office in 1035 after he had fallen out of favour with the Salian Emperor Conrad II. In 1039 Carinthia was inherited by Emperor Henry III himself, who split off the Carniolan march the following year and granted it to Margrave Poppo of Istria. In 1077, the duchy was given to Luitpold, again a member of the Eppensteiner family, which, however, became extinct with the death of Luitpold's younger brother Henry III of Carinthia in 1122. Upon his death the duchy was further reduced in area: a large part of the Eppenstein lands in what is today Upper Styria passed to Margrave Ottokar II of Styria.
The remainder of Carinthia passed from Duke Henry III to his godchild Henry from the House of Sponheim, who ruled as Henry IV, from 1122 to his early death the following year.[1] The most outstanding of the Spanheim dukes was Bernhard, the first Carinthian duke who was actually described and honoured in documents as "prince of the land".[1] The last Spanheim duke was Ulrich III; he signed an inheritance treaty with his brother Archbishop Philip of Spanheim of Salzburg, who, however, could not prevail against the Bohemian king Ottokar II Přemysl. In spite of being supported by the Habsburg king Rudolf I of Germany, who defeated Ottokar II at the Battle on the Marchfeld in 1278, Philip never gained actual power. The duchy was seized by Rudolph and Philip died a year later in 1279.
Habsburgs
Rudolf, after being elected King of the Romans and defeating King Ottokar II, at first gave Carinthia to Count Meinhard II of Gorizia-Tyrol. In 1335, after the death of Henry, the last male of this line, Emperor Louis the Bavarian gave Carinthia and the southern part of the Tyrol as an imperial fief to the Habsburg family on 2 May in Linz. The Habsburgs would continue to rule Carinthia until 1918. As with the other component parts of the Habsburg monarchy, Carinthia remained a semi-autonomous state with its own constitutional structure for a long time. The Habsburgs divided up their territories within the family twice, according to the 1379 Treaty of Neuberg and again in 1564. Each time, the Duchy of Carinthia became part of Inner Austria and was ruled jointly with the adjacent duchies of Styria and Carniola.
Over the centuries, the German language, which carried more prestige, expanded at the expense of Slovene, but the fact that in the 16th century the Estates of Carinthia could still point out that Carinthia was "a WindicArchduchy", i.e. a sovereign Slovene principality, shows that the Carinthian people were aware of their ancient and pre-German roots.
During World War I, Carinthia experienced a relatively high number of war deaths: thirty-seven for every 1,000 inhabitants. This was higher than in most other German-speaking areas of Austria-Hungary (except German South Moravia).[2]
Following the end of the war and the dissolution of Austria-Hungary, the 1919 Treaty of Saint-Germain stipulated the Carinthian Canal Valley stretching from Tarvisio as far as Pontafel (187 square miles)[3] go to Italy and that the Slovene-speaking areas of the Meža Valley, the Drava Valley area around Unterdrauburg, which was afterwards renamed Dravograd, and the Jezersko area (128 square miles of territory)[3] be ceded to the new SHS State. The Kingdom of Serbs, Croats and Slovenes, however, was not satisfied with these parts of the former duchy and also occupied land north of the Karawanks mountain range, including the capital city of Klagenfurt. The Entente powers decided on a two-stage referendum, of which the first stage, the Carinthian Plebiscite was held on 10 October 1920 to determine the fate of Carinthia. The outcome in favour of Austria did not change the borders as decided upon in the Treaty of Saint-Germain.