The flag of Germany is a tricolour consisting of three equal horizontal bands displaying the national colours of Germany: black, red, and gold. The flag was first adopted as the national flag of modern Germany in 1919, during the Weimar Republic.

The black-red-gold tricolour first appeared in the early 19th century and achieved prominence during the 1848 Revolutions. The short-lived Frankfurt Parliament of 1848–1850 proposed the tricolour as a flag for a united and democratic German state. With the formation of the Weimar Republic after World War I, the tricolour was adopted as the national flag of Germany. Following World War II, the tricolour was designated as the flag of both West and East Germany. The two flags were identical until 1959, when the East German flag was augmented with the coat of arms of East Germany. Since reunification on 3 October 1990, the black-red-gold tricolour has remained the flag of Germany.

The flag of Germany has not always used black, red, and gold as its colours. After the Austro-Prussian War in 1866, the Prussian-dominated North German Confederation adopted a tricolour of black-white-red as its flag. This flag later became the flag of the German Empire, formed following the unification of Germany in 1871, and was used until 1918. Black, white, and red were reintroduced as the German national colours with the establishment of Nazi Germany in 1933.

Germany (ⁱ/ˈdʒɜrməni/), officially the Federal Republic of Germany (German: Bundesrepublik Deutschland, pronounced [ˈbʊndəsʁepuˌbliːk ˈdɔʏtʃlant] ( listen)), is a federal parliamentary republic in Europe. The country consists of 16 states while the capital and largest city is Berlin. Germany covers an area of 357,021 km² and has a largely temperate seasonal climate. With 81.8 million inhabitants, it is the most populous member state and the largest economy in the European Union. It is one of the major political powers of the European continent and a technological leader in many fields.

A region named Germania, inhabited by several Germanic peoples, was documented before AD 100. During the Migration Period, the Germanic tribes expanded southward, and established successor kingdoms throughout much of Europe. Beginning in the 10th century, German territories formed a central part of the Holy Roman Empire. During the 16th century, northern German regions became the centre of the Protestant Reformation while southern and western parts remained dominated by Roman Catholic denominations, with the two factions clashing in the Thirty Years' War, marking the beginning of the Catholic–Protestant divide that has characterized German society ever since. Occupied during the Napoleonic Wars, the rise of Pan-Germanism inside the German Confederation resulted in the unification of most of the German states into the German Empire in 1871 which was Prussian dominated. After the German Revolution of 1918–1919 and the subsequent military surrender in World War I, the Empire was replaced by the Weimar Republic in 1918, and partitioned in the Treaty of Versailles. Amidst the Great Depression, the Third Reich was proclaimed in 1933. The latter period was marked by Fascism and World War II. After 1945, Germany was divided by allied occupation, and evolved into two states, East Germany and West Germany. In 1990 Germany was reunified.