Rome was in a state of warfare between noble factions, each of whom had a candidate they regarded as pope. A pope presided at St. Peter’s, another at the Lateran and a third at Saint Mary Major. Two of them, Benedict IX, a scion of the counts of Tusculum, and Sylvester III of the Crescenzi clan, represented rival factions of the Roman nobility. The claim of the third, Gregory VI, was peculiar in that he had purchased the title in good faith from Benedict IX two years previously.[2] Each claimant had a number of supporters in the Roman church and held a portion of the city.
https://en.wikipedia.org/wiki/Council_of_Sutri
