Pier Gerlofs Donia (ca. 1480–1520) was a Frisian rebel leader and pirate. He is best known by his West Frisian nickname Grutte Pier ("Big Pier"; in the pre-1980 West Frisian spelling written as Greate Pier), or by the Dutch translation Grote Pier which referred to his legendary size and strength.
His life is mostly shrouded in legend. Based upon a description now attributed to Pier's contemporary Petrus Thaborita, the 19th-century historian Conrad Busken Huet wrote that Grutte Pier was
|A tower of a fellow as strong as an ox, of dark complexion, broad shouldered, with a long black beard and moustache. A natural rough humorist, who through unfortunate circumstances was recast into an awful brute. Out of personal revenge for the bloody injustice that befell him (in 1515) with the killing of kinsfolk and destruction of his property he became a freedom fighter of legendary standing.|