An opera house is a theatre building used for opera performances that consists of a stage, an orchestra pit, audience seating, and backstage facilities for costumes and set building. While some venues are constructed specifically for operas, other opera houses are part of larger performing arts centers.

The first public opera house was the Teatro San Cassiano in Venice, Italy, which opened in 1637. Italy, where opera has been popular through the centuries among ordinary people as well as wealthy patrons, still has a large number of opera houses. When Henry Purcell was composing, there was no opera house in London. The first opera house in Germany was built in Hamburg in 1678. Early U.S. opera houses served a variety of functions in towns and cities, hosting community dances, fairs, plays, and vaudeville shows as well as operas and other musical events.

In the 17th and 18th centuries, opera houses were often financed by rulers, nobles, and wealthy people who used patronage of the arts to endorse their political ambitions and social positions or prestige. With the rise of bourgeois and capitalist social forms in the 19th century, European culture moved away from its patronage system to a publicly supported system. In the 2000s, most opera and theaters raise funds from a combination of government and institutional grants, ticket sales and, to a smaller extent, private donations.

Coordinates: 52°31′07″N 13°22′06″E / 52.51861°N 13.36833°E / 52.51861; 13.36833

The Kroll Opera House (German: Krolloper) was an opera building in Berlin, Germany, located in the central Tiergarten district on the western edge of the Königsplatz square (today Platz der Republik), facing the Reichstag building. It was built in 1844 as an entertainment venue for the restaurant owner Joseph Kroll. During its eventful history it was redeveloped as an opera house in 1851 and was used by various owners and directors for opera, operetta and drama. It was later operated by the Prussian state opera and drama companies and served as the assembly hall of the German Reichstag parliament from 1933. Severely damaged by bombing and the Battle of Berlin in World War II, it was finally demolished in 1951.

The Kroll story began in the Silesian capital Breslau, where the entrepreneur Joseph Kroll (1797-1848) had opened the “Kroll Winter Garden” in 1837. The Breslau authorities chose this reputable establishment to entertain the new Prussian king Frederick William IV when he visited the city in 1841. The king was impressed by the splendid, flower-decorated rooms and suggested that something similar should be initiated in Berlin to become the social hub for the nobility in the Prussian residence.

Adolf Hitler (German: [ˈadɔlf ˈhɪtlɐ] ( listen); 20 April 1889 – 30 April 1945) was an Austrian-born German politician and the leader of the National Socialist German Workers Party (German: Nationalsozialistische Deutsche Arbeiterpartei (NSDAP), commonly referred to as the Nazi Party). He was chancellor of Germany from 1933 to 1945 and dictator of Nazi Germany (as Führer und Reichskanzler) from 1934 to 1945. Hitler is commonly associated with the rise of fascism in Europe, World War II, and the Holocaust.

A decorated veteran of World War I, Hitler joined the German Workers' Party, precursor of the Nazi Party, in 1919, and became leader of the NSDAP in 1921. In 1923, he attempted a coup d'état, known as the Beer Hall Putsch, in Munich. The failed coup resulted in Hitler's imprisonment, during which time he wrote his memoir, Mein Kampf (My Struggle). After his release in 1924, Hitler gained popular support by attacking the Treaty of Versailles and promoting Pan-Germanism, antisemitism, and anticommunism with charismatic oratory and Nazi propaganda. After his appointment as chancellor in 1933, he transformed the Weimar Republic into the Third Reich, a single-party dictatorship based on the totalitarian and autocratic ideology of Nazism. His aim was to establish a New Order of absolute Nazi German hegemony in continental Europe.