Gregory I, Count of Tusculum

He was the son of Alberic II (son of Alberic I of Spoleto and Marozia), and Alda of Vienne (daughter of Hugh, King of Italy and his second wife, Alda (or Hilda)).

He held the cities of Galeria, Arce, and Preneste and the title count palatine, the palace referred to being that of the Lateran.

As well as being an intimate and ally of the popes, especially Sylvester II, Gregory also served as praefectus navalis of Holy Roman Emperors Otto I and Otto II.

However, on 6 February 1001, he was named "Head of the Republic" by the Romans for leading the revolt against Otto III and expelling the Crescentii.

His death is attested before the 11 June 1012, when his successor, Theophylact, was elected Pope.