Complex sentence: During the War of the Austrian Succession, he was one of the principal Austrian military commanders, and was most notable for his defeat by Frederick the Great at the Battle of Chotusitz, fought in 1742, and the Battle of Hohenfriedberg in 1745.
Split into simpler sentences: During the War of the Austrian Succession, he was one of the principal Austrian military commanders. He was most notable for his defeat by Frederick the Great at the Battle of Chotusitz, fought in 1742, and the Battle of Hohenfriedberg in 1745.