Borgia, Stefano an Italian prelate and theologian, was born at Velletri, Dec. 3, 1731. He early gave evidence of great talent, and received the first of his education from his uncle, archbishop of Fermo. He devoted himself especially to the study of antiquities, and at the age of nineteen was received at the academy of Cortona. He collected a Very rich museum of monuments, medals, manuscripts, etc. Benedict XIV appointed him governor of Benevento, and soon after he was made secretary of the Congregation of the Propagandists, or of foreign missions. Pius VI appointed him cardinal and general inspector of the Foundling Hospital, and he introduced important changes in its administration. He went to Venice to see the men of letters, then to Padua to found an academy, and finally to Valencia to organize a kind of Propagandist society; and was sent to Africa and Asia to bear the principles of religion, and to collect monuments. The pontifical government having been re-established at Rome, in 1800, the new poptiff, Pius VII, who found the, administration in disorder, placed Borgia at the head of the council, the labors of which included nearly all the material interests of the state. In 1801 he was appointed rector of the Roman College. Fatigued with his labors, and an advanced age, he accompanied his master to France to crown Bonaparte, but he was taken ill at Lyons, and died there, Nov. 23, 1804. His museum, rich especially in Egyptian and Indian monuments, was his chief possession. He had sold his jewels to obtain these monuments, and his plate to publish a description of them. They were, however, scarcely his property, but rather that of the learned of his country. Adler, Zaega, Gergi, Paulin of St. Bartholomew, Heeren, and many. — others have profited by this collection, and have written concerning it. The manners of this cardinal were as gentle as his spirit was chaste. Among his principal works we notice, Monumento di Papa Giovanni XVI (Rome, 1750): — Breve Istoria dell' Antica Citta di Tadino nell' Umbria (1751). An ancient map of the world in the museum of this cardinal, prepared by the cure of Camillus, Giovanni Paolo Borgia, nephew of the cardinal, is known in the history of geography under the name of the Mappe Monde du Cardinal Borgia (Encyclop. des Gens du M.). See Hoefer, Nouv. Biog. Generale, s.v.