Geuzen (French: Les Gueux, English: the Beggars) was a name assumed by the confederacy of Calvinist Dutch nobles and other malcontents, who from 1566 opposed Spanish rule in the Netherlands. The most successful group of them operated at sea, and so were called Watergeuzen (French: Gueux de mer, English: Sea Beggars). In the Eighty Years' War, the Capture of Brielle by the Watergeuzen in 1572 provided the first foothold on land for the rebels, who would conquer the northern Netherlands and establish an independent Dutch Republic. They can be considered either as privateers or pirates, depending on the circumstances or motivations.

The leaders of the nobles, who signed a solemn league known as the Compromise of Nobles, by which they bound themselves to assist in defending the rights and liberties of the Netherlands against the civil and religious despotism of Philip II of Spain were Louis, Count of Nassau, and Henry, Count of Bréderode. On April 5, 1566 permission was obtained for the confederates to present a petition of grievances, called the Request, to the regent, Margaret, Duchess of Parma. About 250 nobles marched to the palace accompanied by Louis of Nassau and Bréderode. The regent was at first alarmed at the appearance of so large a body, but one of her councillors, Berlaymont, was heard to exclaim, "What, madam, is your highness afraid of these beggars (ces gueux)?"