-98 AD: Tacitus described the territory of Germania. What is now Berlin, in ancient times was well outside the frontiers of the Roman Empire. Germanic tribes then inhabited the region (some experts argue that Slavic peoples might have been settling there since before the era: see Przeworsk culture). During the post-Roman Migration Period, they departed for other lands, probably to become part of the new ruling class in the invaded areas of the Western Roman Empire. It is not known if there was a permanent settlement at the time in what is today known as Berlin.
-6th century onwards: A certain cultural cluster (i.e. Prague-Korczak culture) of Slavic tribes from the east start moving into the sparsely populated area between the Elbe and Oder rivers.
-About 720: Two Slavic tribes settled in the Berlin region. The Hevelli settled on the river Havel with their central settlement in Brandenburg, which gave the name for the whole territory. The Sprevane settled close to the river Spree in today's district of Berlin-Köpenick.
-About 750: The Hevelli founded Spandow (today's Spandau) on the river Havel. This seems to be the closest settlement to the area which is today known as Berlin.
-About 825: Spandau and Köpenick were protected with barriers. They were the major settlements and later towns in the area until the early 11th century.
-Early 9th century: Slavic tribes settle in vicinity of later city Berlin.
948: Emperor Otto I the Great established German control over the now largely Slavic inhabitants of the area and founded the dioceses of Havelberg and Brandenburg.
-about 950: Margrave Gero led several campaigns against Slavs settled in the area; the vast territory governed by Gero was split after his death in 965 into several marches, Northmarch, Saxon March, Lusatia and more.
-972: Mieszko I defeated Margrave Hodo at Oderberg and Cedynia at the Oder river in the Battle of Cedynia. Later his son Boleslaw I temporarily conquered land "along the sea" (Longum Mare), which in a 1046 imperial document is called Pomerania.
-983: Emperor Otto II died.
-983: In a great uprising the heathen Slavs wiped out German control from the territory of present day Brandenburg. The monasteries were burned, priests and German officials killed or expelled. The Slavic tribes living east of Elbe remained pagan for the next 150 years.
-12th century: German kings and emperors re-established control over the now largely Slavic-inhabited lands. The Slavic inhabitants of the area were either driven out, or became subject to German feudal lords. Many Slavic inhabitants survived the conquests and live there still today, such as the Sorbs and Lusatians. The church brought bishoprics, which with their walled towns, afforded protection for the townspeople from attack. With the monks and bishops, the history of the town of Brandenburg, which in time became the state of Brandenburg, began.
-1134: After the Wendish Crusade, the German magnate Albert the Bear was granted the Northern March by the Holy Roman Emperor Lothar II. For some time up until the 15th century, some part of the area that would become Brandenburg was inhabited by the Slavic Wends, whose descendants still make up a part of the area's modern population. Albert's control of the region was nominal for several decades, but he engaged in a variety of campaigns against the Wends, as well as more diplomatic efforts which saw his control become more real by the middle of the 12th century.
-1150: Albert the Bear formally inherited parts of Brandenburg from its last Wendish prince, Pribislav. His descendants, the Ascanians, then made considerable progress in Christianizing and cultivating the lands. There was never any distinction made by any of the German rulers, and the Slavic and German tribes intermarried.