Crescentius the Younger, or Crescentius II (died 998), son of Crescentius the Elder, was a leader of the aristocracy of medieval Rome. During the minority of Otto III, Holy Roman Emperor he declared himself Patricius Romanorum, Consul or Senator of Rome and made himself de facto ruler of Rome. After being deposed, he led a rebellion, seized control of Rome, and appointed an antipope, but the rebellion failed and Crescentius was eventually executed.