Turning his attention to the east, Henry reduced various Slavonic tribes to subjection, took Brennibor, the modern Brandenburg, from the Hevelli, and secured both banks of the Elbe for Saxony.
To the east of the Saxons were the Polabs (Polabi) in the basin of the Elbe, and beyond them the Hevelli about the Havel.
The history of Brandenburg begins when the German king, Henry the Fowler, defeated the Havelli, or Hevelli, and took their capital, Brennibor, from which the name Brandenburg is derived.