By the 8th century, Slavic Wends, such as the Sprevjane and Hevelli, had started to move into the Brandenburg area and had intermarried with Saxons and Bohemians.The Bishoprics of Brandenburg and Havelberg were established at the beginning of the 10th century (in 928 and 948, respectively).

They were suffragan to the Archbishopric of Mainz; the Bishopric of Brandenburg reached to the Baltic Sea.King Henry the Fowler had started governing in the region in 928–9, allowing Emperor Otto I to establish the Northern March under Margrave Gero in 936 during the German Ostsiedlung.

However, the march and the bishropics are overthrown by a Slavic rebellion in 983; until the collapse of the Liutizian alliance in the middle of the 11th century, the Holy Roman Empire government through bishoprics and marches comes nearly to a standstill for approximately 150 years, even though the bishopric is retained.