[4] In 1086 he married the widow Gertrude of Brunswick,[3] which allowed him to unite her inheritance of property from the Brunonen dynasty and from the counts of Katlenburg to his Northeimer Länderei.
From the counts of Bilstein Henry inherited parts of the Werra Valley, where he became the sole landholder.
[6] In 1086 he and his brothers, Kuno and Otto, changed sides to support Emperor Henry IV.
[7] Henry's wife, Gertrude, was the only sister of Egbert II, Margrave of Meissen, whose own marriage remained childless.
These Frisian counties, however, had been annexed from Egbert during the latter's rebellion in 1089 and were being administered by Conrad, Bishop of Utrecht.