The Battle of Warns (West Frisian: Slach by Warns; Dutch: Slag bij Warns) was a battle of the Friso-Hollandic Wars between Count William IV of Holland and the Frisians which took place on 26 September 1345. The annual commemoration of the battle is important for many nationalist Frisians. The Frisians won the battle and repelled the Dutchmen from the eastern coast of the Zuiderzee.



The Friso-Hollandic Wars, also called Frisian-Hollandic Wars (Dutch: Fries-Hollandse Oorlogen; West Frisian: Frysk-Hollânske oarloggen), were a series of short medieval wars (ranging from single battles to entire campaigns) consisting of the attempts made by the counts of Holland to conquer the free Frisian territories, which lay to the north and east of their domain. These wars were waged off and on from 1256 to 1297, 1324 to 1348, 1396 to 1411, and from 1421 to 1422, although it could be argued that a state of war continued to exist between the County of Holland and the Frisian territories till well after the year 1500.