This square was laid out between 1741 and 1743, under the rule of King (König) Frederick the Great. The buildings surrounding it were largely destroyed by the Allied air raids over Berlin, and were rebuilt in the 1950s.
To the left of the picture is the Berlin State Opera (Berliner Staatsoper), first built between 1741 and 1742, and reconstructed in 1843, after a fire destoyed it. Almost 100 years later, the Allies would cause heavy damage to the building in two air raids, first in 1941 (the Staatsoper was repaired and reopened the following winter) and then in February 1945. The Opera House reopened ten years later.
To tle right can be seen part of Berlin Royal Library and Altes Palais.
The Berlin Royal Library (model by Emperor Heer 99) was built between 1775 and 1780 by architect Georg Christian Unger, after a design by Joseph Fischer von Erlach. After the construction of the nearby Berlin Staatsbibliothek (Unter den Linden 8). It's now part of Humboldt University.