Ottokar I (; c. 1155 – 1230) was Duke of Bohemia periodically beginning in 1192, then acquired the title of King of Bohemia, first in 1198 from Philip of Swabia, later in 1203 from Otto IV of Brunswick and in 1212 (as hereditary) from Frederick II. He was one of the most eminent members of the Přemyslid dynasty. Early years Ottokar's parents were Vladislaus II, Duke of Bohemia, and Judith of Thuringia. His early years were passed amid the anarchy that prevailed everywhere in the country. After several military struggles, he was recognized as ruler of Bohemia by Holy Roman Emperor Henry VI in 1192. He was, however, soon overthrown for joining a conspiracy of German princes to bring down the Hohenstaufen dynasty. In 1197, Ottokar forced his brother, Duke Vladislaus III Henry, to abandon Bohemia to him and to content himself with Moravia. Taking advantage of the civil war in Germany between the Hohenstaufen claimant Philip of Swabia and the Welf candidate Otto IV, Ottokar declared himself King of Bohemia in 1198, being crowned in Mainz. This title was supported by Philip of Swabia, who needed Czech military support against Otto. In 1199, Ottokar divorced his wife Adelheid of Meissen, a member of the Wettin dynasty, to marry Constance of Hungary, the young daughter of Hungarian King Béla III. In 1200, with Otto IV in the ascendancy, Ottokar abandoned his pact with Philip of Swabia and declared for the Welf faction. Otto IV and later Pope Innocent III subsequently accepted Ottokar as the hereditary King of Bohemia. Golden Bull of Sicily Ottokar was quickly forced back into Philip's camp by the imperial declaration of a new duke of Bohemia, Děpolt III. Subject to his recognition as duke, Ottokar had to allow his divorced wife to return to Bohemia. Having been completed this condition, he again ranged himself among Philip's partisans and still later was among the supporters of the young King Frederick II. In 1212 Frederick granted the Golden Bull of Sicily to Bohemia. This document recognised Ottokar and his heirs as Kings of Bohemia. The king was no longer subject to appointment by the emperor and was only required to attend Diets close to the Bohemian border. Although a subject of the Holy Roman Empire, the Bohemian king was to be the leading electoral prince of the Holy Roman Empire and to furnish all subsequent emperors with a