Orsini was elected member of the Roman Constituent Assembly in 1849, and after the fall of the revolutionary republic in Rome he conspired against the papal autocracy in the interest of the Mazzinian party. Mazzini sent him on a secret mission to Hungary, but he was arrested in 1854 and imprisoned at Mantua. He escaped a few months later using a tiny saw to cut through two grids of bars, climbed out of the window 100 feet above ground and slid down using a rope he had made of bedsheets. Passing as a sympathetic peasant, he managed to get past the Austrian guards.