Gregory V, né Bruno von Kärnthen (c. 972 – February 18, 999), Pope from May 3, 996 to February 18, 999, son of the Salian Otto I, Duke of Carinthia, who was a grandson of the Emperor Otto I the Great (936–973). Gregory V succeeded Pope John XV (985–996), when only twenty-four years of age. He was the chaplain of his cousin, Emperor Otto III (983–1002), who presented him as candidate.
Politically Gregory V acted consistently as the Emperor's representative in Rome and granted many exceptional privileges to monasteries within the Holy Roman Empire. One of his first acts was to crown Otto III Emperor on May 21, 996. Together they held a synod a few days after Otto III's coronation, in which Arnulf was ordered to be restored to the See of Reims, and Gerbert, the future Pope Silvester II (999–1003), was condemned as an intruder. Robert II of France (996–1031), who had been insisting on his right to appoint bishops, was ultimately forced to back down, and ultimately also to put aside his wife Bertha, by the rigorous enforcement of a sentence of excommunication on the kingdom.
Until the council of Pavia (997) Gregory V had a rival in the person of the antipope John XVI (997–998), whom Crescentius II and the nobles of Rome had chosen, in revolt against the will of the youthful Emperor Otto III, the Pope's cousin. The revolt of Crescentius II was decisively suppressed by the Emperor, who marched upon Rome. John XVI fled, and Crescentius II shut himself up in the Castel Sant'Angelo. The Emperor's troops pursued the antipope, captured him, cut off his nose and ears, cut out his tongue, blinded him, and publicly degraded him before Otto III and Gregory V. He was sent to the monastery of Fulda, in Germany, where he lived until 1013. The Castel Sant'Angelo was besieged, and when it was taken, Crescentius II was hanged upon its walls (998).