Throughout these events, the area of today's Berlin contained small fishing and farming villages.
After 1200: Under the grandsons of Albert the Bear, Otto and Johann, two towns, Cölln in 1237 and Berlin in 1244, were founded on the banks of the river Spree. The name of Cölln may have been chosen, due to involvement of the Archbishopric of Cologne bringing in settlers from the Rhine river area (as far north as Friesland) to build up the marshy territory along the Spree river. Later Berlin and Cölln were united into one city; one of Berlin's modern-day boroughs is Neukölln, named after Cölln.
The heraldry of the House of Ascania ruling in Brandenburg, the red eagle and the black bear(s), were part of the constitution of Berlin, depicted in continuous documents ever since. The heraldic bear is documented in many other towns ruled by the House of Ascania and other cities of the Holy Roman Empire at that time, such as Bern.
-28 October 1237: Cölln is first mentioned in documents.
-1244:Berlin is first mentioned in documents.
-1251: First mention of city rights for Berlin.
-1253: First known Berlin seal document with Brandenburg red eagle.
-1261: First mention of city rights for Cölln.
-1280: First surviving Berlin seal document depicting 2 upright bears with Brandenburg eagle in center
-Documents are exhibited in the cathedral museum in the town of Brandenburg an der Havel.
Berlin's name is recorded in Latin language documents as "Berolina". The etymology of the name is uncertain, but may be related to the Old Polabian stem berl-/birl- "swamp".
-1307: Twin cities Berlin and Cölln formed a trading union on political and security matters, and participated in the Hanse. Their urban development took place in parallel for 400 years.
-Around 1400: Berlin and Cölln had 8,000 inhabitants.
Not much is left of these ancient communities, although some remainders can be seen in the Nikolaiviertel, near the Rotes Rathaus, and the Klosterkirche, close to today's Alexanderplatz. A great town center fire in 1380 damaged most written records of those early years, as well as the great devastation of the Thirty Years War and further war destruction.