Complex sentence: In 1514, the weakened old King Vladislaus II faced a major peasant rebellion led by György Dózsa, which was ruthlessly crushed by the nobles, led by János Szapolyai.
Split into simpler sentences: In 1514, the weakened and aging Vladislaus faced a major peasant rebellion led by György Dózsa. It was ruthlessly crushed by the Hungarian nobles led by János Szapolyai.