The Annibaldi were a powerful baronal family of Rome

Rome

Rome is the capital of Italy and the country's largest and most populated city and comune, with over 2.7 million residents in . The city is located in the central-western portion of the Italian Peninsula, on the Tiber River within the Lazio region of Italy.Rome's history spans two and a half...

 and the Lazio in the Middle Ages

Middle Ages

The Middle Ages is a periodization of European history from the 5th century to the 15th century. The Middle Ages follows the fall of the Western Roman Empire in 476 and precedes the Early Modern Era. It is the middle period of a three-period division of Western history: Classic, Medieval and Modern...

. It began to rise to prominence in the 13th century with the favour of Popes Gregory IX

Pope Gregory IX

Pope Gregory IX, born Ugolino di Conti, was pope from March 19, 1227 to August 22, 1241.The successor of Pope Honorius III , he fully inherited the traditions of Pope Gregory VII and of his uncle Pope Innocent III , and zealously continued their policy of Papal supremacy.-Early life:Ugolino was...

 and Alexander IV

Pope Alexander IV

Pope Alexander IV was Pope from 1254 until his death.Born as Rinaldo di Jenne, in Jenne , he was, on his mother's side, a member of the de' Conti di Segni family, the counts of Segni, like Pope Innocent III and Pope Gregory IX...

, in the hollow left by the Counts of Tusculum

Counts of Tusculum

The counts of Tusculum were the most powerful secular noblemen in Latium, near Rome, in the present-day Italy between the 10th and 12th centuries. Several popes and an antipope during the 11th century came from their ranks. They created and perfected the political formula of noble-papacy, wherein...

. In the late years of the same century they were however overwhelmed by the Caetani

Caetani

Caetani, or Gaetani, is the name of an Italian noble family princely family which played a great part in the history of Pisa and of Rome, principally via their close links to the papacy.-Origins:...

.

The family's most outstanding figure was Riccardo (1210-1276), who was created cardinal in 1237 by Gregory IX, and bought the fief of Molara. Other family lines than that originated by Riccardo where those of Monte Compatri

Monte Compatri

Monte Compatri is a comune in the Province of Rome in the Italian region Latium, located about 20 km southeast of Rome on the Alban Hills. It is one of the Castelli Romani.-History:...

, Castel Zancato and of the Coliseum. Another cardinal of the family was Annibaldo (1220-1272), a friend of Albertus Magnus

Albertus Magnus

Albertus Magnus, O.P. , also known as Albert the Great and Albert of Cologne, is a Catholic saint. He was a German Dominican friar and a bishop, who achieved fame for his comprehensive knowledge of and advocacy for the peaceful coexistence of science and religion. Those such as James A. Weisheipl...

 and Thomas of Aquino. Riccardo was the first protector of the Augustinian Order.