Girolamo Mattei was an Italian nobleman of the House of Mattei and Duke

Duke

A duke or duchess is a member of the nobility, historically of highest rank below the monarch, and historically controlling a duchy...

 of Giove.

Mattei was born in 1606, the son of Asdrubale Mattei

Asdrubale Mattei

thumb|Portrait of Asdrubale Mattei di Giove by students of Caravaggio .Asdrubale Mattei , Duca di Giove, was an Italian nobleman of the House of Mattei, an avid art collector and a patron of Caravaggio.-Family:...

, Marquis di Giove, and his wife Costanza Gonzaga (of the House of Gonzaga

House of Gonzaga

The Gonzaga family ruled Mantua in Northern Italy from 1328 to 1708.-History:In 1433, Gianfrancesco I assumed the title of Marquis of Mantua, and in 1530 Federico II received the title of Duke of Mantua. In 1531, the family acquired the Duchy of Monferrato through marriage...

). He was the older brother of Luigi Mattei

Luigi Mattei

Luigi Mattei was an Italian military General and Marquis de Belmonte. During the 17th century he commanded troops loyal to the papal armies of Barberini Pope Urban VIII and Pamphili Pope Innocent X during the Wars of Castro.-Biography:...

; Marquis di Belmonte

Belmonte Calabro

Belmonte Calabro, known simply as Belmonte prior to the proclamation of the Kingdom of Italy, is a town and comune in the province of Cosenza, in Calabria...

 and military ally of the Barberini

Barberini

The Barberini are a family of the Italian nobility that rose to prominence in 17th century Rome. Their influence peaked with the election of Cardinal Maffeo Barberini to the papal throne in 1623, as Pope Urban VIII...

 and Pope Urban VIII

Pope Urban VIII

Pope Urban VIII , born Maffeo Barberini, was pope from 1623 to 1644. He was the last pope to expand the papal territory by force of arms, and was a prominent patron of the arts and reformer of Church missions...

. He was the nephew of Ciriaco Mattei

Ciriaco Mattei

Ciriaco Mattei was an Italian nobleman of Rome and of the House of Mattei and one of the most prolific art collectors of his time.-Family:...

 and Cardinal Girolamo Mattei

Girolamo Mattei

Girolamo Mattei was an Italian Cardinal from the House of Mattei.Mattei was born 8 February 1547, the son of Alessandro Mattei and Emilia Mazzatosta. He was the younger brother of Ciriaco Mattei and the older brother of Asdrubale Mattei, Marquis di Giove...

.

In 1643, Pope Urban VIII issued a papal bull

Papal bull

A Papal bull is a particular type of letters patent or charter issued by a Pope of the Catholic Church. It is named after the bulla that was appended to the end in order to authenticate it....

 recognising Giove as a Duchy

Duchy

A duchy is a territory, fief, or domain ruled by a duke or duchess.Some duchies were sovereign in areas that would become unified realms only during the Modern era . In contrast, others were subordinate districts of those kingdoms that unified either partially or completely during the Medieval era...

 of the Mattei, thus making Girolamo Mattei, Duca di Giove. His bull was issued with the words, affinchè la terra sia adorna al titolo più degno (roughly: that the earth is adorned with those more worthy of title).

In 1666 he married Eugenia Spada (1639 - 1717), sister of Cardinal Fabrizio Spada

Fabrizio Spada

Fabrizio Spada was an Italian Cardinal of the Roman Catholic Church, and served as Secretary of State under Pope Innocent XII.-Life:...

. He had at least one child, Alessandro Mattei (1670 - 1729), who inherited his father's titles.