He was the son of , a noted military commander. He was raised in an intellectual atmosphere and studied at the
Collegium Nobilium. In 1780, he became an
Assessor and was later elected a member of the
Great Sejm. In 1790, he was a
Podstoli for the
Masovian Voivodeship and also became a
Castellan in
Raciąż, thereby gaining a place in the . He was a supporter of the
Patriotic Party and helped create the
Friends of the Constitution. In 1792, together with
Julian Ursyn Niemcewicz and , he published the ''''. During the period of the
Targowica Confederation he left Poland; eventually arriving in Paris, where he became a mediator in talks between Polish emigrants and French revolutionary authorities. After the defeat of the
Girondists, he was imprisoned but soon released and allowed to return home. There, he found himself persecuted and detained by
Jacob von Sievers, a deputy of Empress
Catherine the Great. In 1794, he joined the
Kościuszko Uprising; becoming a member of the
Provisional Council of the Duchy of Masovia and the
Supreme National Council. When the uprising collapsed, he was taken into house arrest in
Saint Petersburg. He was released following an amnesty in 1795 and, in 1797, he once again went to Paris. He remained there until 1802, then established himself at what is now known as the
Mostowski Palace, which he had inherited in 1795. He also resumed his publishing enterprise, with the latest equipment brought in from Paris. He was in France again for much of 1812. Later that year, he became the Minister of the Interior for the
Duchy of Warsaw. From 1815 to 1830, he served as the presiding minister for the Government Commission for Internal Affairs of
Congress Poland. While in that position, he helped promote construction of the
Augustów Canal and established the (
Agronomic Institute) in
Marymont. During those years, he remained active as a writer; publishing literary criticism and theatre reviews in numerous Warsaw journals. He was also an honorary member of the
Warsaw Society of Friends of Learning. In 1825, he was appointed to the Senate. During the
November Uprising, he absented himself from that body's meetings. When the uprising had been quashed, the Russian authorities allowed him to emigrate to France, where he owned lands inherited from his father. He died there ten years later, and was interred at
Montmartre Cemetery. His first wife was the writer,
Anna Olimpia Przeździecka, whom he married in 1787 and divorced in 1804. He was her second husband and they had no children. His second marriage, to Marianna Potocka (1780-1837), a member of the noble
Potocki family, produced five children. == References ==