The Siege of Alkmaar was a turning point in the Eighty Years' War. The burghers fought the Spanish (who had set up their camp in Oudorp) with boiling tar and burning branches from their renewed city walls. This battle was a turning point in the war, when the Spanish commander, Don Fadrique, the son of the hated Alva himself, was defeaten and retreated. Combatants Dutch rebels Spanish Empire The Eighty Years War, or Dutch Revolt (1566–1648), was the revolt of the Seventeen Provinces in the Netherlands against the Spanish king. ... Tar is a viscous black liquid derived from the destructive distillation of organic matter. ... Don Fadrique Alvarez de Toledo was commander of the Spanish troops during the most bloody phase of the Dutch Revolt. ... Fernando Álvarez de Toledo, Duke of Alva. ...