The 1834 Quadruple Alliance united Britain, France, Spain, and Portugal to expel absolutist pretenders and marked a liberal bloc against the Holy Alliance powers.
Key Facts
- Date signed
- 22 April 1834
- Signatories
- UK, France, Spain, Portugal
- Primary targets
- Infante Miguel (Portugal) and Infante Carlos (Spain)
- Additional articles signed
- August 1834, to aid Spanish legitimist government
- Key dynastic outcome
- Support for Isabella II against Carlist pretender Carlos María Isidro
- Spain's alliance departure
- Ended Spain's membership of the Holy Alliance
Location
Cause → Event → Consequence
Dynastic crises in Portugal and Spain, where absolutist pretenders Miguel and Carlos threatened liberal constitutional governments, created pressure for the liberal monarchies of Britain and France to intervene diplomatically and prevent the spread of absolutism on the Iberian Peninsula.
On 22 April 1834, the United Kingdom, France, Spain, and Portugal signed the Quadruple Alliance, committing the four powers to expel Infante Miguel from Portugal and Infante Carlos from Spain. Additional articles added in August 1834 extended mutual military support to the liberal government in Spain against Carlist forces.
The alliance provided critical diplomatic and military backing for Isabella II's government, contributing to the defeat of the Carlists in the First Carlist War. It also ended Spain's association with the Holy Alliance and established an unprecedented entente between Britain and France, effectively giving them informal influence over Iberian affairs.
Political Outcome
The four liberal powers agreed to expel absolutist pretenders from Portugal and Spain, supporting constitutional monarchies and weakening the Holy Alliance's influence on the Iberian Peninsula.
Iberian Peninsula under competing absolutist and liberal factions; Spain nominally part of Holy Alliance
Liberal constitutional governments backed by Britain and France; Spain exits Holy Alliance; Carlist pretender weakened