[2] She was rumored to have had an affair with the Russian ambassador to Poland, Nikolai Vasilyevich Repnin, who was alleged to have fathered her son Adam George Czartoryski.

In Paris in 1772, she met Benjamin Franklin, subsequently a leader of the American Revolution, and the French philosophers Jean-Jacques Rousseau and Voltaire, who were bringing new ideas to the old order.

While in Prussia with her daughter Maria Wirtemberska for the latter's marriage, she told Frederick II of her fears that her husband would be poisoned, which was what had caused a split between him and Stanisław August Poniatowski politically.

Among the first objects to be included were Turkish trophies that had been seized by Polish King John III Sobieski's forces at the 1683 Battle of Vienna.

Izabela's son Adam George Czartoryski, going into exile in Paris, evacuated the museum's surviving objects to the Hôtel Lambert.