The Frisian Kingdom was a Frisian realm which existed from 650 to 734 AD, with Dorestad and Utrecht serving as its capitals. The Frisians, a Germanic people descended from the Angles, Saxons, and Jutes, resettled in the Low Countries, where the Frisii once lived. The Frisians became rivals with the Franks to the south, and the Frankish victory at the 695 AD Battle of Dorestad led to the Franks conquering Dorestad, Utrecht, and Vechten from the Frisians. In 695, the Catholic Church established a mission in Utrecht, beginning the Christianization of Frisia. The Frisian king Redbad took advantage of the Frankish succession dispute of 714 to defeat the Franks at Cologne in 716, but he died in 719 before he could invade Francia with his massive army. In 734, the Frankish ruler Charles Martel invaded Frisia and defeated the Frisians at the Battle of the Boarn, annexing Frisia into Francia. Frisia was later conquered by Rorik Hemmingsson, but, as the Vikings and Franks repeatedly assaulted the kingdom, King Rorik was forced to take an oath of loyalty to the Franks and return to vassal status.
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