Mattia Jona, Master Drawings and Prints, Japanese Prints - Piazzetta Guastalla 5, 20122 Milan, Italy, tel (+39) 02 8053315

CESARE PROVAGGI (Active in Italy, XIX century) MARIA DE MEDICI WITH RUBENS IN HIS STUDIO
Watercolour, signed 'Provaggi f'; 230 x 290 mm.
The watercolour depicts Rubens in his studio, working at the painting 'the Death of Henry IV and the Proclamation of the Regency'. In front of him Maria de' Medici, the wife of Henry IV of France, who commissioned the celebrated cycle of twenty-four paintings, now at the Louvre. Twenty-one of the paintings depict Marie's own struggles and triumphs in life. The remaining three are portraits of herself and her parents.

I wasn't able to find any information about Provaggi, but it's quite interesting to note that a few other watercolors by him, depicting Flemish painters in their studios, were on the art market in the last years.