Officially, the 1st of December is a public holiday in the country, to commemorate the restoration of Portuguese independence.
Between the late 16th century until the mid-17th century, Portugal was under the Iberian Union with Spain. This led to Portugal being ruled by three generations of Spanish Kings, which are known in our history as the “Filipes” as all three Kings (Philip II, Philip III, Philip IV) who ruled Portugal, had the same first name. What set the stage for Spanish rule was a dynastical crisis brought on by the actions of the young Portuguese King, Sebastian I. At the tender age of 3, Sebastian became King of Portugal, inheriting a vast colonial empire from his grandfather, King John III.
At age of 21 king Sebastian made the fateful decision of invading Morocco on crusade a campaign that would end in a crushing defeat in the battle of Alcacér-Quibir. No one knows what became of Sebastian. He disappeared in battle, giving rise to legends over centuries that we would return on a misty day to save his Kingdom.
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The three main claimants to the throne were Catarina de Bragança, Don António Prior do Crato, and Philip II of Spain (a relative of Sebastião), an ambitious King who sought to add Portugal to his vast empire.
Philip II came to rule Portugal, through an astute combination of diplomacy and sheer brute force. The “Philippine era” would be initially positive for Portugal. However, during the first half of the 17th century the Spanish empire entered a period of decline. The Dutch and the English seized various Spanish and Portuguese colonial possessions and the Spanish Empire was struggling with the Dutch Revolt and the Thirty Years’ War. Discontent was brewing in Portugal.
The Portuguese nobility stood to lose considerable power and influence, so a group of nobles known as the Forty Conspirators organized a coup against the Spanish forces with the end goal of placing John, the 8th Duke of Braganza, on the Portuguese throne. The coup was carried out on the 1st of December 1640. The Forty Conspirators killed the Secretary of State, Miguel de Vasconcelos, and imprisoned Margaret of Savoy, cousin to the King himself and ruler of Portugal in his name. John of Braganza would be acclaimed by the people of Lisbon on the same day, and would subsequently reign as King John IV.
The timing of the execution was specifically chosen to coincide with Spanish campaigns in the Thirty Years’ War and efforts to quell a revolt in Catalonia, thus allowing the new King time to consolidate his rule and mount a defence before the Spanish could act against Portugal. The ensuing conflict would last 28 years, and would be marked by various border skirmishes and raids. However, there were five major battles during the War of Restoration, namely: the Battle of Montijo (1644), the Battle of Lines of Elvas (1659), the Battle of Ameixial (1663), Battle of Castelo Rodrigo (1664), and the last major engagement was the Battle of Montes Claros (1665).
All of these battles are commemorated in the Obelisk at the centre of Lisbon’s Restauradores Square. Portugal also relied on diplomatic and military aid from England, who wanted to undermine Spanish hegemony in continental Europe, and when an alliance with France was secured, the Spanish would be forced to sign the Treaty of Lisbon in February 1668, recognizing the house of Braganza as the Royal dynasty of Portugal and putting an end to a conflict between two neighbours.