The Erosion of Portuguese Autonomy Under Spanish Rule (1598–1640)

When Philip II of Spain became King of Portugal in 1580, the Iberian Union was established under the agreement that Portugal would retain its autonomy, with its own laws, institutions, and government. However, after his death in 1598, his successors, Philip III and Philip IV, gradually eroded Portuguese independence, culminating in widespread discontent that eventually led to the Portuguese Restoration War (1640–1668).

Philip III (r. 1598–1621): The Beginning of Decline

• Upon his accession, Philip III of Spain (also King of Portugal as Philip II) gradually abandoned his father’s policy of respecting Portuguese autonomy.
• Unlike Philip II, who had resided in Portugal, Philip III rarely visited—his only trip was in 1619, near the end of his reign.
• He appointed Spaniards to the six-member Portuguese governing council, violating the terms of the Iberian Union.
• Over time, Portuguese nobles and officials were increasingly replaced by Spaniards, weakening local governance and alienating the Portuguese elite.

Philip IV and the Misrule of the Duke of Olivares (1621–1640)

• Philip IV (r. 1621–1665) had little interest in ruling Portugal and delegated control to his chief minister, Gaspar de Guzmán, the Count-Duke of Olivares.
• Olivares, an advocate of centralized Spanish rule, sought to fully integrate Portugal into Spain, disregarding its legal and political autonomy.

Policies That Led to Portuguese Resentment

1. Heavy Taxation and Military Requisitions

   • Spain was engaged in multiple wars, particularly against France and the Dutch Republic, and Olivares forced Portugal to bear a heavy tax burden.
   • Portuguese troops and resources were drained to support Spain’s military efforts, further weakening Portuguese defenses in its colonies.

2. Suppression of Portuguese Nobility

   • Many Portuguese nobles lost power and influence, as Olivares favored Spaniards for high-ranking positions.
   • The hispanophile elite, once supportive of the Iberian Union, turned against Spanish rule.

3. Colonial Vulnerability

   • As Spain focused on European wars, Portugal’s overseas empire became vulnerable to Dutch, English, and French attacks.
   • The Dutch captured major Portuguese colonies, including parts of Brazil (1630) and Ceylon (1638).
   • Portuguese merchants and colonial administrators blamed Spain for neglecting Portugal’s global interests.

4. Attempts to Abolish Portuguese Autonomy

   • Olivares sought to fully integrate Portugal into Spain, eliminating its separate institutions.
   • He proposed a unified Iberian military force, further fueling fears of Portuguese subjugation.

The Road to Revolt: Growing Calls for Independence

• By the late 1630s, resistance to Spanish rule had grown across all levels of Portuguese society:
  • The nobility resented their loss of power.
  • The merchant class was angered by economic decline and colonial losses.
  • The general population suffered from high taxes and forced military service.
• Secret meetings among Portuguese nobles began plotting for an independence movement.

Conclusion: The Path to the Portuguese Restoration War (1640–1668)

The disrespect for Portuguese autonomy under Philip III and Philip IV, coupled with economic strain and military overreach, created widespread resentment that ultimately led to the Portuguese revolt in 1640.

The mismanagement of Portugal by the Count-Duke of Olivares proved to be the final breaking point, setting the stage for the end of the Iberian Union and the restoration of the Portuguese monarchy under the House of Braganza.