Her salon was the center of the noble amateur theatre, which flourished in Stockholm in the 1720s- and 1730s and is estimated to have played a part in the establishment of the first Swedish language professional theater at Bollhuset in 1737.

During the Swedish Age of Liberty, when absolute monarchy had been abolished in favor of a parliamentary system after the Great Northern War, it was noted that women participated in the political debate and party strife, promoting their opinions in public in a different way than had previously been the case, examples being Hedvig Mörner, Magdalena Elisabeth Rahm and Henrika Juliana von Liewen, and it was even said that women were the true leaders of the political parties.

[1] Foreign powers participated in political life through their ambassadors by recruiting agents to forward their agenda and supporting party factions with subsidies.

In 1733 Olof von Dahlin caricatured the political Swedish salon hostess in Den Swänska Argus as "Fru Kättia Sällskapslik" (Mrs Lusty Society) and condemned her for "laughing at virtue" by spending so much time with men and exchanging flirtatious jokes with them.

[12] After the death of Daniel Niklas von Höpken in 1741, De la Gardie became the informal leader and central figure of the Carl Gyllenborg faction within the Hats Party government.

After the death of her spouse in 1741, Hedvig Catharina De la Gardie settled in Paris in France in the company of her daughter Brita Sophia, where she converted to Roman Catholicism, which was at that point formally a crime in Sweden.

She reportedly spent million livres in France, participated in aristocratic high society life, being described as a daily guest at the royal court at the Palace of Versailles.