Key Facts
- Duration
- 1910–1926 (16 years)
- Number of presidencies
- 8 presidents
- Number of ministries
- 45 ministries in 16 years
- Peak population
- ~5,969,056
- Mainland area
- ~92,391 km²
- Ended by
- 28 May 1926 military coup
Imperial Zenith Metrics
Historical Trajectory
Phase I: Rise
The First Portuguese Republic emerged from the 5 October 1910 revolution, which overthrew the constitutional monarchy of King Manuel II. Republican and liberal forces, dissatisfied with monarchical instability and clerical influence, led the revolt and proclaimed a republic. A new constitution was adopted in 1911, separating church and state and establishing a parliamentary system, though political factionalism quickly undermined coherent governance from the outset.
Phase II: Zenith
Portugal entered World War I in 1916 on the Allied side, partly to secure its colonial possessions in Africa and gain international legitimacy for the republic. The colonial empire in Africa and Asia remained largely intact throughout this period, and some modernizing reforms in education and civil liberties were introduced, though persistent economic difficulties and political violence prevented the republic from achieving stable democratic consolidation.
Phase III: Decline
Chronic instability, with 45 governments in 16 years, widespread strikes, military interventions, and economic hardship eroded public confidence in republican institutions. A succession of coups and counter-coups culminated in the 28 May 1926 military coup led by General Gomes da Costa, which dissolved the republic and established the Ditadura Nacional. This military dictatorship subsequently gave way to António de Oliveira Salazar's Estado Novo authoritarian regime.
Notable Imperial Reigns
Selected rulers mapping the empire’s trajectory