(1558–1630). Italian biographer and writer on art, who initiated a new kind of treatise, influential in 17th-century Europe, which was aimed at the noble amateur, or connoisseur, rather than the practitioner. He came to Rome from his native Siena in 1592, where he became physician to Pope Urban VIII, and cultivated the friendship of many painters. His Considerazioni, written in 1619, contains biographies, and information for the collector on such questions as how to buy and make judgements on works of art, how to hang a collection, how to distinguish a copy from an original, or how to determine a work's date or origin. His Viaggio per Roma, written in 1623–4 (published 1923), was a new type of guidebook, with an emphasis on works of art. Mancini wrote on Poussin, and produced the first biographies of Caravaggio and Annibale Carracci. An ebullient personality, he was an atheist and adulterer, and made clever use of his official position to further his activities as art dealer.
From The Oxford Companion to Western Art in Oxford Reference.