Matteo Rosso Orsini

Matteo Rosso Orsini, called the Great, was a Roman noble of the Orsini family, a friend of Saint Francis of Assisi and protector of the Franciscan order. In 1241 Pope Gregory IX named him senator of Rome, and during that year's sede vacante he was the city's effective lord, confining the cardinals in the Septizodium to force the papal election.

He opposed Emperor Frederick II's Italian campaigns and defeated him in 1243. He greatly enlarged the Orsini estates and died in 1246; his son became Pope Nicholas III.