She was involved with the struggles for Italian unification in the 1840s and her older son Vittorio Emmanuele would unify Italy.
Her Wikipedia article is here. She was the daughter of Maria Luisa of Naples and Sicily, grandaughter of Queen Maria Carolina who was the daughter of Empress Maria Theresia. She was, by her father Ferdinand III, Grand Duke of Tuscany, the granddaughter of Holy Roman Empress Maria Luisa of Spain and Empress Maria Theresia's son Leopold. Maria Luisa of Spain was the daughter of Queen Maria Amalia.