From Wikipedia

Secret Files Of The Inquisition
Episode Four

End Of Inquisition

During the reign of Charles IV, in spite of the fears that the French Revolution provoked, several events took place that accentuated the decline of the Inquisition. In the first place, the state stopped being a mere social organizer and began to worry about the well-being of the public. As a result, they considered the land-holding power of the Church, in the señoríos and, more generally, in the accumulated wealth that had prevented social progress. On the other hand, the perennial struggle between the power of the throne and the power of the Church, inclined more and more to the former, under which, Enlightenment thinkers found better protection for their ideas. Manuel Godoy and Antonio Alcalá Galiano were openly hostile to an institution whose only role had been reduced to censorship and was the very embodiment of the Spanish Black Legend, internationally, and was not suitable to the political interests of the moment:

The Inquisition? Its old power no longer exists: the horrible authority that this bloodthirsty court had exerted in other times was reduced... the Holy Office had come to be a species of commission for book censorship, nothing more...

In fact, prohibited works circulated freely in the public bookstores of Seville, Salamanca or Valladolid.

The Inquisition was abolished during the domination of Napoleon and the reign of Joseph I (1808–1812). In 1813, the liberal deputies of the Cortes of Cádiz also obtained its abolition, largely as a result of the Holy Office's condemnation of the popular revolt against French invasion. But the Inquisition was reconstituted when Ferdinand VII recovered the throne on July 1, 1814. It was again abolished during the three year Liberal interlude known as the Trienio liberal. Later, during the period known as the Ominous Decade, the Inquisition was not formally re-established, although, de facto, it returned under the so-called Meetings of Faith, tolerated in the dioceses by King Ferdinand. These had the dubious honour of executing the last heretic condemned, the school teacher Cayetano Ripoll, garroted in Valencia on July 26 1826 (presumably for having taught deist principles), all amongst a European-wide scandal at the despotic attitude still prevailing in Spain. Juan Antonio Llorente, who had been the Inquisition's general secretary in 1789, became a Bonapartist and published a critical history in 1817 from his French exile, based on his privileged access to its archives.

The Inquisition was definitively abolished on July 15, 1834, by a Royal Decree signed by regent Maria Cristina de Borbon, a liberal queen, during the minority of Isabel II and with the approval of the President of the Cabinet Francisco Martínez de la Rosa. (It is possible that something similar to the Inquisition acted during the First Carlist War, in the zones dominated by the Carlists, since one of the government measures praised by Conde de Molina Carlos Maria Isidro de Borbon was the re-implementation of the Inquisition to protect the Church). During the Carlist Wars it was the conservatives who fought the progresists who wanted to reduce the Church's power amongst other reforms to liberalise the economy.