Giovanni Battista Rinuccini (1592–1653) was an Italian Roman Catholic archbishop in the mid-seventeenth century. He was a noted legal scholar and became chamberlain to Pope Gregory XV. In 1625 Pope Urban VIII made him the Archbishop of Fermo in Italy. In 1645 Pope Innocent X sent him to Ireland as Papal Nuncio. He brought money and weapons to help the Confederate Irish in its conflict against the English Parliamentarians. Rinuccini became the dominant figure of the hard-line Clerical Faction of the Confederates refusing the alliance with the Irish Royalists.