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Adelbrik Adelen (Sexbierum, elected about 830) was the third potestaat (magistrate governor) of Friesland a province of the Netherlands.
He was potestaat during the government of Lorraine, and defeated the Vikings. In Kollum he won a victory over a Swedish duke. There is a source that indicates that he is a brother or a cousin of the Utrecht BishopFrederik, who came from the same Friesian village of Sexbierum.
The family emblem of Adelen is a Friese eagle half left, and right on a blue field up with a key above. To the upper left and right is a 5-pointed star.
References
Wopke Eekhoff Beknopte geschiedenis van Friesland, in hoofdtrekken 1851 p 490