Princess Konstancja Poniatowska (1759âÂÂ1830) was a Polish noblewoman from the House of Poniatowski. She was also the niece of King Stanisà Âaw August Poniatowski.
Konstancja Poniatowska was born on 2 March 1759 in Warsaw, Poland. She was the only daughter of Kazimierz Poniatowski and his wife; Apolonia Ustrzycka. Konstancja had an elder brother, Stanisà Âaw Poniatowski (1754âÂÂ1833). Konstancja later married Ludwik Skumin Tyszkiewicz on 4 April 1775. Konstancja was a close friend of the French Minister of Foreign Affairs, Charles Maurice de Talleyrand-Périgord.
On 26 March 1779 Konstancja gave birth to Anna Tyszkiewicz. She was the only child of the couple.