Magnus Forteman (809) was the legendary first potestaat (or magistrate governor) and commander of Frisia which is now part of Germany and the Netherlands. His existence is based on a saga's writings.
According to one of these sagas, he was the first of the 17 potestates of Frisia in the period after the kings of Frisia, a period of Charlemagne until Albert of Saxony (800–1498).
The saga relates that Magnus was the leader of the army of Frisians in the conquest of Rome. The eyes of Pope Leo III were pulled out[1] and he was expelled from Rome by a group of nobles who did not accept his authority. With 700 "discerning" Frisians, Magnus reconquered Rome from these nobles. They entered Rome at night by a small port that had become visible through low water level in the Tiber. Through the Flavian gardens, they went to St. Peter's and when they were discovered there a battle ensued. Magnus flew his banner clearly visible on top of the church, creating confusion. There were no prisoners, and the Frisians were in Saint Peter's Square up to their ankles in blood.
According to the legend, the Frisians elected Magnus, that is all Frisian freemen the born as well as the unborn, as long as the wind blows the clouds and the world lasts.[clarification needed] Also Charles gave them a golden crown in the shield, and a half eagle in their coat of arms, as a token that they had received freedom from the Emperor.[2]
According to the legend, Magnus was the founder of Church of Santi Michele e Magno, the Friezenkerk in Rome.[citation needed] His father was said to be Gustavus Forteman who founded the first Christian church in 777 in Friesland, the Cathedral of Almenum. Also Gustavus Forteman is fictional. Magnus was killed fighting against the Saracens.
Generally this story is considered as a myth and the Karelsprivilege as a forgery, although the acclaimed proviledge were confirmed by the Holy Roman Emperors William II (13th century) and Sigismund (15th century).[3] Also Jancko Douwama mentions the conquest of Rome by Magnus, the risk and reward in the form of the Karelsprivilege in his "Book of the Parties" in 1525.
M. Kist en H. Kist and H. Wind, Een man van eer, Bloemlezing uit Jancko Douwama's geschriften, Uitgeverij Verloren, Hilversum, 2003 (a man of honour, Anthology of Jancko Douwama's writings)
Theun de Vries, Fryske Sêgen III, Leeuwarder Courant 15 January 1927, volume 3 (Enigszinds romantiseerd)
F. Binkes, Over eene volkplanting der Friesen in Zwitserland, beneevens eenige aanmerkingen over den tocht der Friesen naar Rome, In: De Vrije Fries, episode I (1839), blz. Binkes, Over eene volkplanting der Friesen in Switzerland, beneevens every criticisms over den der Friesen trip to Rome, In: The Free Frisian, I episode (1839), p. 1 t/m 63. 1 to 63. Also available digitally [1].
MP v. MP V. Buijtenen, De grondslag van de Friesche Vrijheid (Assen 1953) (16) Buijtenen, (The basis of the Friesian Liberty) (Assen 1953) (16)
T. van der Laars, Wapens, vlaggen en zegels van Nederland (weapons, flags and seals in the Netherlands), Amsterdam (1913), reprinted 1989, page 58
K. v. V. Richthofen, Untersuchungen II (Berlin 1882), 147-315 Richthofen,
