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In page Theda Ukena:

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Born into House of Ukena, ruling family of Neermoor and Leer, Theda was the granddaughter and heiress of the chief Focko Ukena (died 1436) and was born in 1432 in Oldersum as the daughter of Uko Fockena, Governor of Oldersum, and his wife, Hebe Attena von Dornum (1396-1449) She was probably named after her grandmother Theda of Reide, the first wife of Focko Ukena. Her father was assassinated in June 1432.[citation needed]