Why did Ferdinand VII revoke the Salic Law of Succession in Spain?

Ferdinand VII revoked the Salic Law of Succession primarily to ensure that his own offspring could inherit the Spanish throne, regardless of gender.12

The Salic Law, introduced in 1713 to prevent the union of the Spanish and French crowns, had previously barred women from royal succession. Although Ferdinand’s predecessor, Charles IV, had made an unpublished decision to revoke this law in 1789, it remained legally contested.12

By issuing the Pragmatic Sanction on March 29, 1830, Ferdinand formally promulgated this revocation. This move was intended to secure the succession for his unborn child with his fourth wife, María Cristina, thereby bypassing the claims of his brother, Don Carlos. The birth of his daughter, Isabella II, later that year solidified this intent, though the dispute over the law's validity ultimately triggered the First Carlist War.123