Later, the Marquis du Châtelet sold the Lambert to Claude Dupin and his wife Louise-Marie Dupin, who continued the tradition of the salon. The Dupins were ancestors of writer George Sand, who, because of her relationship with the Polish composer Chopin, was also a frequent guest of the 19th-century Polish owners of the property. A political salon In 1843, the hôtel particulier was bought by Prince Adam Jerzy Czartoryski, member of the powerful family of Polish magnates. He and his brother, Konstanty Adam, were leaders of the liberal aristocratic faction of the Great Emigration from Poland, following the collapse of the November Uprising of 1830–1831. A political group formed around Adam Czartoryski, and his palatial residence in central Paris, surrounded by the natural 'moat' of the river Seine, lent its name to his political faction. The political beliefs of the Hôtel Lambert faction were derived from the 3 May Constitution, which its members had supported. The Hôtel Lambert played an important role in keeping the "Polish question" alive in European politics, by continually keeping the Polish cause on the agenda. It also served as a safe harbour for Polish emigés and royalists, exiled from their country after the unsuccessful uprising against Russia. Among other notable politicians who took part in the Hôtel Lambert's activities were Władysław Czartoryski, son of Adam, Józef Bem, Henryk Dembiński, Karol Kniaziewicz, Julian Ursyn Niemcewicz, Władysław Stanisław Zamoyski, Władysław Ostrowski and Leon Kaplinski. Initially a political think tank and a discussion club, the political faction also worked on the preservation and promotion of Polish culture. An Historical and Literary Society began in 1832 and the idea of a Polish library, which exists to this day just along the Quai d'Orleans nearby, was conceived in the Hôtel Lambert in 1838. Plans laid for two schools teaching Polish (one for girls, one for boys) and were established in Batignolles. There was support for numerous commercial enterprises, especially in the fields of publication and printing. Over time, it became one of the most important hubs of Polish culture in the world, especially after the January Uprising, when Polish language and culture became heavily persecuted during the enforced Russification in the Russian Partition of Poland itself. The Hôtel Lambert drew some renowned politicians and artists of the epoch, including Alexandre Walewski, Charles Forbes René de Montalembert, Frédéric Chopin, Zygmunt Krasiński, Alphonse de Lamartine, George Sand, Honoré de Balzac, Hector Berlioz,