Complex sentence: Upon his ascension to the papal throne in 1592, he immediately had several noble troublemakers put to death, including most famously Troio Savelli, scion of a powerful ancient Roman family, and the youthful and noble Beatrice Cenci, who had murdered her father.
Split into simpler sentences: Upon his ascension to the papal throne in 1592, he immediately had several noble troublemakers put to death, including most famously Troio Savelli, scion of a powerful ancient Roman family. He also did not spare the youthful and noble Beatrice Cenci, who had murdered her father.