Luisa Carlotta was born at the Palace of Portici, the eldest child of King Francis I from his second wife, Infanta María Isabella of Spain.

Luisa Carlotta played an important role during the sickness of Ferdinand VII to ensure that her niece, Isabella, became heiress to the Spanish throne instead of her uncle Carlos.

When the king Ferdinand VII was suffering from a very severe gout attack that many feared would end his life (1832), a huge variety of characters, including the ambassador of Naples and her own confessor, harassed the Queen of Spain to persuade her to renounce the dynastic rights of her daughters in favor of Carlos, to avoid the horrors of a civil war.

When the Counsel of Castile, an organization that favored a transition towards constitutionalism, learned about this, they sent word to Luisa Carlotta who was famous for her determination and strong personality, in hopes that she could persuade the queen to change her mind again.

Luisa Carlotta rode nonstop after receiving the news and arrived to La Granja, unannounced, four days after the Pragmatic Sanction had been repealed.