House of La Tour d'Auvergne
Her mother was from the House of La Tour d'Auvergne, her father being the last Count of Boulogne from the aforementioned House. Her maternal grandmother Jeanne de Bourbon-Vendôme was a direct patrilineal descendant of Louis, the first duke of Bourbon. This made Catherine a direct descendant of Louis IX of France, and of the House of Capet, albeit through a female line. Also this made her a 7th cousin, once removed of her husband Henry and a 6th cousin, 3 times removed of Henri of Navarre, her son-in-law.