The Union of Utrecht was a treaty signed in 1579 that united several northern provinces of the Netherlands in their struggle for independence from Spanish rule. This agreement marked a significant step in the Dutch Revolt, which sought to break free from the oppressive governance of King Philip II of Spain. The Union established a framework for cooperation among the provinces, promoting mutual defense and shared governance. It is often considered a foundational moment in the formation of the Dutch Republic, which would later become a major European power in trade and culture during the Golden Age.