In the early sixteenth century, Friesland was under the authority of George, Duke of Saxony. However, Charles, Duke of Egmond or Guelders, was also keen on possessing the Frisian region, resulting in a battle between their supporters. After George, Duke of Saxony, had given the territory to Charles of Egmond, yet another war broke out, this time between the Frisians and Holland. This war formed the backdrop for the rise of Pier Gerlofs Donia (circa 1480–1520), better known as Grutte Pier (Great Pier). Grutte Pier and his sword have become an inseparable duo, symbols of the Frisian struggle for independence.
Pier, a farmer from Kimswerd, had managed to elude the war until Saxon soldiers burnt down his farm in 1515. Pier and his companions in adversity decided to take up arms against first, the Saxon oppressors and later, against Holland, forming an armed band called ‘Arumer Zwarte Hoop’ (‘Black Gang from Arum’). Pier became leader of the ‘seinschipsluyden’ and fought as a pirate in battles on the Zuiderzee, capturing many English and Dutch ships. Frisians regard him as a freedom fighter, but to the Dutch he is an outlaw.