Key Findings:

• Ferdinand VII remained King of Spain having been acknowledged on 11 December 1813 by Napoleon in the Treaty of Valençay.
• The remaining afrancesados were exiled to France.
• The whole country had been pillaged by Napoleon's troops.
• The Catholic Church had been ruined by its losses and society subjected to destabilizing change.
• With Napoleon exiled to the island of Elba, Louis XVIII was restored to the French throne.
• British troops were partly sent to England, and partly embarked at Bordeaux for America for service in the final months of the American War of 1812.

After the Peninsular War, the pro-independence traditionalists and liberals clashed in the Carlist Wars, as King Ferdinand VII ("the Desired One"; later "the Traitor King") revoked all the changes made by the independent Cortes Generales in Cádiz, the Constitution of 1812 on 4 May 1814. Military officers forced Ferdinand to accept the Cádiz Constitution again in 1820, and was in effect until April 1823, during what is known as the Trienio Liberal.

Portugal's position was more favorable than Spain's. Revolt had not spread to Brazil, there was no colonial struggle and there had been no attempt at political revolution. The Portuguese Court's transfer to Rio de Janeiro initiated the independence of Brazil in 1822.

The war against Napoleon remains as the bloodiest event in Spain's modern history.