Disregarding the Pragmatic Sanction, Frederick began the Silesian Wars shortly after taking the throne. Although the inexperienced king retreated from the battle, the Prussian Army achieved victory over Austria in the Battle of Mollwitz (1741) under the leadership of Field Marshal Schwerin. The Prussian cavalry under Schulenburg had performed poorly at Mollwitz; the cuirassiers, originally trained on heavy horses, were subsequently retrained on more maneuverable, lighter horses. The hussars and dragoons of General Zieten were also expanded. These changes led to a Prussian victory at Chotusitz (1742) in Bohemia, and Austria conceded Silesia to Frederick with the Peace of Breslau.