'', a 19th century painting by
Jan Matejko. Piattoli is one of many historical characters featured on this canvas. See
here for a detailed legend. Piattoli developed contacts with notable figures on the Polish political scene, initially from the group opposed to the royal faction. By the end of his stay in Paris, he likely became a supporter of reforms in France and Poland, and begun taking his first serious steps in political activism, through the involvement in the Quattuowirat, a group of magnates planning a (never realized)
confederacy. He became a foreign member of the
Société des Amis des Noirs. Through his freemason contacts with Pierre Maurice Glayre, Piattoli won the confidence of Poland's King
Stanisław August Poniatowski, becoming his agent in Paris and, by the end of 1789, his
private secretary and librarian, although without any official title. Acting as a sort of cultural aide, Piattoli, who had strong ties to the reformist and often anti-royal opposition, became an important link between the reformers —
Ignacy Potocki in particular — and the king. In the words of a Swedish diplomat, L. Engstrom, he was "like a tireless spring", constantly mediating between the two factions. Due to his association with the reformers, in conservative Rome, he became infamous as a staunch supporter of revolutionary ideals and was accused of "democratism".
Vatican diplomats criticised the king for hiring such a "revolutionary", but the king defended Piattoli quite vividly. In any case, many such claims were exaggerations or rumours spread by his political enemies: according to one such rumour, Piattoli was alleged to incite crowds in France to kill the king. In reality, Piattoli supported the
Monarchiens of the
French Revolution's early stages, but more in the direction of peaceful transformation into a constitutional republic than the
regicidal excesses. Between 1790 and 1792, Piattoli was sent on several sensitive
diplomatic missions for the king to
Berlin and other places. He was involved in the negotiations of the
Polish-Prussian alliance. He collaborated with Ignacy Potocki, helping draft many texts connected with Potocki's work in the
Sejm, the
legislature of the
Polish–Lithuanian Commonwealth. He was also an active supporter of Poniatowski's plan for a
hereditary succession. Piattoli, as Poniatowski's secretary and a resident of the
Royal Castle in
Warsaw, has been credited with winning the King over to the idea of
social reforms and with playing a part in the drafting of the
Constitution of 3 May 1791. The exact nature of Piattoli's role in regard to the Constitution remains uncertain; modern historians disagree to what degree he was an executor, a mediator, or an initiator. He played a role in convincing the King to collaborate with the leaders of the
Patriotic Party on drafting a constitution. He might have prepared or expanded drafts of the document, based on discussions among the principal authors, including the King,
Hugo Kołłątaj (another politically active Roman Catholic priest) and Ignacy Potocki. At a minimum, he seems to have helped catalyze the process. Historian
Emanuel Rostworowski describes him as a vital secretary-editor, who certainly participated in related discussions and influenced both Potocki and the king, and calls Piattoli's quarters in the Royal Palace a "creche" of the constitution. Piattoli was, finally, involved in the final preparations for the vote that took place during the Sejm session on 3 May. Later that month he became a founder of the
Friends of the Constitution. He was active in various political causes and worked closely with other key figures in Poland such as Hugo Kołłątaj. He became a trusted adviser to
Dorothea von Medem, Duchess of Courland. He supported reforms to improve the status of the
burghers and
Jews. == Final years ==