"Liudolf of Brunswick (c. 1003 – 23 April 1038) was Margrave of Frisia, Count of Brunswick, Count in the Derlingau and the Gudingau.
Liudolf was a descendant of the Saxon family of the Brunonen. He was a son of Bruno I, Count of Brunswick, and Gisela of Swabia. The later Roman Emperor Henry III was his half-brother. He married Gisela and had four children. He controlled the Frisian counties Oostergo, Zuidergo and Westergo. For two more generations the Brunonen family line inherited the title. How the Brunonen came to their position in the counties is not known. There is a theory that Liudolf took advantage of the reign of violence by the Counts of Holland in the part of Friesland between the Vlie and the Lauwers. Not much is known about his life. He died in 1038 and was succeeded by his son, Bruno II." - (en.wikipedia.org 02.11.2019)
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