COSTA, PIETRO (183o-188o), Italian dramatist, was born at Rome. After fighting for the Roman republic in 1849, he emi grated to South America, but soon returned to Italy, and lived precariously as a literary man until 1870, when his reputation was established by the unexpected success of his first acted tragedy, Nerone. From this time to his death in 1880 Cossa continued to produce a play a year, usually upon some classical subject. His last piece, 1 Napolitani nel 1799, was produced in 1880.