In July 1794 he and several other activists were exiled from Leipzig, and Piattoli was soon arrested by the Austrian authorities. After the failure of the Kościuszko Insurrection later in 1794, many prisoners were set free, but Piattoli was kept imprisoned, together with Kołłątaj, as the Russian authorities insisted that the two were “extremely dangerous”. Hence, even after the final Partitions of the Polish–Lithuanian Commonwealth in 1795, Piattoli was kept interned in Prague by the Austrian Empire authorities until 1800, despite requests for his release from Poniatowski and even Napoleon Bonaparte. His release in 1800 seems to have been the result of efforts of the Czartoryski family and Duchess Dorothea.
