Answer
Henry II supported Duke Jaromír in his struggle against Duke Soběslav I. Jaromír was the older brother of Soběslav, but Soběslav had been made Duke by King Vratislav II. Jaromír was the rightful heir to the throne, but he was not popular with the nobility. Soběslav was a more capable leader and he was able to defeat Jaromír in battle.