When the male line of Blanca's family died out at the death of her uncle, Alfonso Carlos, Duke of San Jaime, some of the Carlists recognized her as the legitimate heiress to the Spanish throne.

After the war ended badly, crushing Don Carlos' hopes of taking the throne of Spain, the family lived mostly in the Parisian district of Passy.

Her father went to live in his palace in Venice, while her mother retired to Tenuata Reale, an estate in Viareggio, Italy inherited in 1879 from Blanca's great-grandmother, Duchess Maria Teresa of Parma.

The newlyweds settled in Lemberg, Galicia, then in Agram, Croatia and finally in Vienna, following Archduke Leopold Salvator's military appointments.

The marriage was happy and produced ten children: Until World War I, Blanca and her large family had a pleasant uncomplicated existence moving according to the seasons among their various residences.

Blanca was forced to ask her cousin Alfonso XIII, who belonged to the rival branch of the Spanish Bourbons, for permission to live in Barcelona.

Alfonso XIII allowed them to come to Spain on the condition that they did not support the claims to the Spanish throne of Blanca's brother Infante Jaime, Duke of Madrid.

Blanca was left under strained economical means, living from vineyards at La Tenuata Reale at Viareggio and from a small rent provided by the Carlist party of Catalonia.

In early 1935 a minoritarian branch of Carlism, the so-called “Cruzadistas” later to be named Carloctavistas, staged a grand meeting in Zaragoza; the gathering adopted a declaration that Doña Blanca was in position to transmit legitimate monarchical hereditary rights from her father, the Carlist king Carlos VII, to her sons.