Prospero Orsi, also referred to as Prosperino delle Grottesche (1560s–1630s) was an Italian painter of the late-Mannerist and early-Baroque period, active mainly in Rome.
Baglione recounts that during the papacy of Sixtus V, Prospero was one of the many artists that decorated the Scala Sancta walls and ceilings with frescoes.
In the benediction loggia of San Giovanni Laterano, he depicted an episode in the Life of Constantine.
While he initially was a close follower of the Cavaliere d’Arpino, he later became allied with Michelangelo da Caravaggio.
[3] Baglione states:[4] That after some time, I know not for what reason, they (Orsi and Arpino) came to have little affection, and he (Orsi) became one of the Dragoman (translator for the exotic and foreign) of Michelangelo da Caravaggio, and was contrary to the Cavaliere as much as possible when he worked.His date of birth is unclear, Baglione describes him as young (20-30s?)