Henry Bretislav was elected on 25 March 1182 as successor of the late bishop of Prague Valentin,[1] and went to Mainz to receive affirmation by Metropolitan Christian I.

In 1192, Ottokar usurped the Bohemian throne from Wenceslaus II, allied with his younger brother Vladislaus Henry, Prince of Brno and Znojmo, whom he appointed Margrave of Moravia.

When Ottokar joined a revolt of several German princes against the ruling House of Hohenstaufen, he and his brother and Vladislaus Henry were declared deposed in June 1193 by a decision of the Imperial Diet at Worms.

Ottokar was abandoned by the nobility and fled; the emperor exempted his cousin Bishop Henry Bretislav from the payment and enfeoffed him with the Bohemian duchy.

Shortly afterwards, he came to terms with his brother Ottokar, who finally ascended the Prague throne and the next year obtained the royal title from Philip of Swabia, confirmed by the German king Frederick II in the 1212 Golden Bull of Sicily.