Since Charles Frederick was the last reigning Duke of Oels, the Duchy fell to the Crown of Bohemia as a vacant fief.

After lengthy negotiations, Silvius Nimrod was invested on 15 December 1648 in Vienna with the Duchy of Oels, in exchange for 20000guilders and the Moravian Lordship of Jevišovice.

Silvius Nimrod then began rebuilding the Duchy, which had suffered during the Thirty Years' War.

In accordance with his last will and testament, Duke Christian of Liegnitz-Brieg took up the guardianship of Silvius Nimrod's underage children.

To prevent an imperial guardianship, which would probably imply a Catholic education, Christian sent the young princes to Tübingen, where they studied at the Collegium illustre.