Geuzen was a name assumed by the confederacy of Calvinist Dutch nobles, who from 1566 opposed Spanish rule in the Netherlands. The most successful group of them operated at sea, and so were called Watergeuzen. 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.