Dietrich was the ancestor of a comital branch named after the residence of
Haldensleben in
Eastphalia. He may have been a son of Count
Wichmann the Elder and Frederuna, sister of Queen
Matilda, and held large estates along the
Elbe and
Saale rivers. A henchman of the royal
Ottonian dynasty, Dietrich in 953 supported King
Otto I of Germany against his revolting son Duke
Liudolf of Swabia. He also fought - without success - against the
Polabian Slavs settling on the Elbe river at the eastern rim of his Eastphalian home territory. In return Otto,
Holy Roman Emperor since 962, appointed him margrave in the Northern March beyond the Elbe, the largest part of the former
Marca Geronis after its dissolution upon the death of Margrave
Gero in 965. Dietrich was a harsh overlord. Together with Archbishop
Adalbert of Magdeburg he enforced the
Christianization of the local Slavic population and was instrumental in the execution of his rival
Gero, Count of
Alsleben. Owing to his pride as stated by the chronicler
Thietmar of Merseburg (he allegedly once refused the marriage of one of his kinswoman to a Slav "dog"), in 983 the Slavic
Lutici and
Hevelli tribes sacked the lands of the eastern bishoprics of
Havelberg and
Brandenburg and reverted to paganism. According to the medieval chroniclers
Adam of Bremen and
Annalista Saxo, Dietrich was deprived of his march in the same year, though he later again appeared as a Saxon general and supported the minor king
King Otto III of Germany against the claims to the throne raised by the Bavarian duke
Henry the Wrangler. According to the
Annals of Quedlinburg, Dietrich died on 25 August 985. ==Issue==