The First Carlist War was a civil war in Spain from 1833 to 1840, the first of three Carlist Wars. It was fought between two factions over the succession to the throne and the nature of the Spanish monarchy: the conservative and devolutionist supporters of the late king's brother, Carlos de Borbón (or Carlos V), became known as Carlists (carlistas), while the progressive and centralist supporters of the regent, Maria Christina, acting for Isabella II of Spain, were called Liberals (liberales), cristinos or isabelinos. It is considered by some authors the largest and most deadly civil war of the period. The Carlist forces were split in three geographically distinct armies: ('North'), and ('Catalonia'), which by and large operated independently from each other. Aside from being a war of succession about the question of who was the rightful successor to Ferdinand VII of Spain, the Carlists' goal was the return to a traditional monarchy, while the Liberals sought to defend the constitutional monarchy. Portugal, France, and the United Kingdom supported the regency, and sent volunteer and even regular forces to confront the Carlist army. Historical background At the beginning of the 19th century, the political situation in Spain was extremely problematic. During the Peninsular War, the Cortes of Cádizwhich served as the Regency for the deposed Ferdinand VII collaborated on the Spanish Constitution of 1812. After the war, when Ferdinand VII returned to Spain (1814), he annulled the constitution in the Manifesto of Valencia, and became an absolutist king, governing by decrees and restoring the Spanish Inquisition, abolished by Joseph I, brother of Napoleon I. The 1805 Battle of Trafalgar had all but shattered the Spanish navy, with the Peninsular War leaving Spanish society overwhelmed by continuous warfare and badly damaged by looting. While the Spanish Empire collapsed, the maritime trade in the Americas and Philippines fell to a trickle, and Spain's military struggled to keep their colonies, with Mexico getting its independence in 1821. The overseas revenue was at a historic low, the royal coffers were empty. Balancing the books and recruitment to the military became an overriding concern for the Spanish Crown, with the governments under King Ferdinand VII failing to provide new solutions or stability. During the Trienio Liberal (1820-1823), the progressives, who were allied to the business classes, resorted to international money lenders in an attempt to avert the economic meltdown Spain was facing. They turned to