Pietro da Cortona was one of the geniuses of the Roman Baroque and was well known for his painting and architecture, although he never painted frescoes in a building he designed. Some of his notable buildings are Santa Maria della Pace in Rome (pictured above) and SS. Luca e Martina (shown below in context of its proximity to the ancient Roman Forum).
Pietro da Cortona was well-known for his fresco paintings as well, including the Allegory of Divine Providence and Barberini Power in the Barberini Palace and Allegories of Virtues and Planets fresco in the Pitti Palace in Florence. Both of these works seek to emphasize the power and importance of the family for which they were painted (the Barberini family and Medici family, respectively). The Pitti Palace frescoes particularly masterfully combine painting and stucco work to provide a seamless unity between the art and the architecture. Pietro da Cortona's skill in combining painting and stucco work were especially influential in Italy and France (Web Gallery of Art, http://www.wga.hu/frames-e.html?/bio/p/pietro/cortona/ biograph.html).
Ceiling fresco with Medici coat of arms, part of the Allegories of Virtues and Planets series, http://en.wahooart.com/A55A04/w.nsf/Opra/BRUE-8LT59U
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