sentences:  It was created by Emperor Frederick Barbarossa in 1180 when he raised the March of Styria to a duchy of equal rank with neighbouring Carinthia and Bavaria, after the fall of the Bavarian duke Henry the Lion earlier that year.Margrave Ottokar IV thereby became the first Duke of Styria and also the last of the ancient Otakar dynasty.As Ottokar had no issue, he in 1186 signed the Georgenberg Pact with the mighty House of Babenberg, rulers of Austria since 976, after which both duchies should in perpetuity be ruled in personal union.