The House of Alvensleben is an ancient, Low German (niederdeutsch) noble family from the Altmark region, whose earliest known member, Wichard de Alvensleve, is first mentioned in 1163 as a ministerialis of the Bishopric of Halberstadt. The family name derives from Alvensleben Castle. They are one of the oldest extant German aristocratic families.

The Bishopric of Havelberg was a Roman Catholic diocese founded by King Otto I of Germany in 946, from 968 a suffragan to the Archbishops of Magedeburg. A Prince-bishopric (Hochstift) from 1151, Havelberg as a result of the Protestant Reformation was secularised and finally annexed by the margraves of Brandenburg in 1598.