John XVII (died December, 1003), born John Sicco, and the son of another John Sicco, was born in the region of Rome then referred to as Biveretica. He succeeded Pope Silvester II (999–1003) as Pope on May 16, 1003, but died less than six months later. John XVII was nominated to the papacy by John Crescentius, a Roman noble who held power in the city in opposition to Emperor Otto III (983–1002). John XVII's successor, Pope John XVIII (1004–09), was also selected by Crescentius.