The numerous studies of the painter Giovan Battista Vanni have not, so far, examined in depth his relations with Florentine patrons and with the various circles he came into contact with, primarily that of the Barberini family in Rome. From the time of his second stay in Rome the painter enjoyed the protection and hospitality of a member of the Florentine Corsi family, identified for the first time in the present article as Monsignor Lorenzo Corsi (1601-1656). With the aid of unpublished documents, account books and letters, the relationship between the two men has been reconstructed and new works have been added to the artist's catalogue. Vanni executed numerous paintings for Corsi, some of them with unusual and highly original themes. Corsi's biography is also reconstructed; he was vice-legate in Avignon, had relations with the Barberini family and with the Francophile party in Rome, where he had important offices. His life was characterized by his close relationship with the Medici family, especially with Cardinals Carlo and Giovan Carlo, with whom he shared artistic tastes, cultural tendencies and a passion for music, rare flowers and garden design. Ferdinando II de' Medici entrusted him with two prestigious legations in France, one at the time of the birth of Louis XIII and another for the death of Maria de' Medici. For almost three years, from 1627 to 1630 (although not continuously), Vanni lived in the Roman residence of Lorenzo Corsi, where the prelate assembled a collection of paintings and where Vanni painted in a room with a skylight specially installed for him by his patron. Probably as a result of Corsi's protection, Vanni also obtained commissions from the Barberini family. Relations between the two continued even after the time he spent in Rome and up until the death of Corsi in 1656. In the later years of his life the Florentine monsignore commissioned the artist a painting with an unusual iconography; this work is an important addition to the artist's catalogue and confirms Corsi's close ties with the Barberini family and France. The painting, which in the present paper retains the title with which it was recorded in the payment made for it, 'Cardinali guerreggianti', depicts Giulio Mazzarino, Richelieu and Cardinals Francesco and Antonio Barberini junior and can be interpreted as a tribute not only to the two cardinals, nephews of Pope Urban VIII (for whom the painting may originally have been intended), but also to Mazzarino's political skills and diplomatic activity in general, by those, like Corsi, who aspired to the highest clerical offices. According to the author's reconstruction, in this work, certainly on the request of his client, Vanni was making reference to the first diplomatic achievement of Mazzarino who in October 1630, on horseback and invoking peace, charged through the French and Spanish armies who were besieging Casale Monferrato. This event, part of the so-called Guerra di Valtellina, one of the consequences of the succession of the city of Mantova – which proved to be a springboard for Mazzarino's extraordinary career in France, bringing him to the attention of Richelieu – was not only recorded in contemporary documents and described in the cardinal's biography written by Elpidio Benedetti, his secretary, but was also represented in earlier iconographies: a scene from the frescoes decorating the so-called Passaggetto di Urbano VIII in the Palazzo del Quirinale in Rome, a French medal by Jean Warin and a print representing Mazzarino on horseback on the battlefield in front of Casale. The great picture of the 'Cardinals', which still belongs to Corsi's descendants, shows Vanni as a painter of historical facts and emblematically reflects the environment in which Monsignor Corsi and the artist lived.
The artist executed other paintings for Corsi in Rome, as is documented by inventories belonging to the prelate's house. These works, as yet untraced, show the choice of original themes, such as the one representing a 'Mago', documented in 1627. Anticipating tendencies that Salvator Rosa would express years later, they reflect Vanni's interest in themes related to magic used in Roman art of the time and in particular by Angelo Caroselli, who also worked for the Barberini family. In Corsi's picture gallery in Rome we also find paintings with religious and devotional themes, like an episode of Saint Benedict's miracles, or his copies of famous works, like that of Titian's Ludovisi “Baccanale”, or paintings like that of a “Bevone”, probably close to themes in the painting of Bamboccio.
The unpublished letters between Lorenzo Corsi and his “maestro di casa” provide further information on the works which Vanni executed in Rome and offer an interesting insight into relations between artists and patrons in seventeenth-century Rome and the state of precariousness in which less prominent artists often lived. A newly identified painting executed for Corsi dating from this period, and belonging to the same collection of paintings as that of the 'Cardinals', is 'Haggar and the Angel', a subject repeatedly depicted by Vanni and stylistically similar to the 'Saint Sebastian Cared for by the Pious Women' for the church of San Giovanni dei Fiorentini in Rome. As is often the case in Vanni's art, these two works show the influence of Correggio, who the artist studied in Parma, sometimes filtered by Lanfranco. The third unpublished painting by Vanni presented in this essay is a 'Holy Family with the Young Saint John', also painted for Corsi, which clearly shows the influence of Pietro da Cortona, another reference appearing in many of the artist's works.