The Twelve Years' Truce was a ceasefire during the Eighty Years' War between Spain and the Dutch Republic, agreed in Antwerp on 9 April 1609 and ended on 9 April 1621. While European powers like France began treating the Republic as a sovereign nation, the Spanish viewed it as a temporary measure forced on them by financial exhaustion and domestic issues and did not formally recognise Dutch independence until the Treaty of Westphalia in 1648. The Truce allowed Philip III of Spain to focus his resources elsewhere, while Archdukes Albert and Isabella used it to consolidate Habsburg rule and implement the Counter-Reformation in the Southern Netherlands.

The Eighty Years' War or Dutch Revolt was an armed conflict in the Habsburg Netherlands between disparate groups of rebels and the Spanish government. The causes of the war included the Reformation, centralisation, excessive taxation, and the rights and privileges of the Dutch nobility and cities.