Third Reich
The building caught fire on 27 February 1933, under circumstances still not entirely known (see Reichstag fire). This gave a pretext for the Nazis to suspend most rights provided for by the 1919 Weimar Constitution in the Reichstag Fire Decree in an effort to weed out communists and increase state security throughout Germany.
During the 12 years of National Socialist rule, the Reichstag building was not used for parliamentary sessions. Instead, the few times where the Reichstag convened at all, it did so in the Krolloper building, a former opera house opposite the Reichstag building. This applies as well to the session of 23 March 1933, in which the Reichstag disposed of its powers in favour of the Nazi government in the Enabling Act, another step in the so-called Gleichschaltung ("coordination"). The building (which was unusable after the fire) was instead used for propaganda presentations and, during World War II, for military purposes. It was also considered for conversion to a flak tower but was found to be structurally unsuitable.
The building, having never been fully repaired since the fire, was further damaged by air raids. During the Battle of Berlin in 1945, it became one of the central targets for the Red Army to capture due to its perceived symbolic significance. Today, visitors to the building can still see Soviet graffiti on smoky walls inside as well as on part of the roof, which was preserved during the reconstructions after reunification.
Read more about this topic: Reichstag (building)