At the end of World War I the Austro-Hungarian Empire was divided back up into two separate countries again, those of Austria and Hungary respectively. The Hapsburgs were replaced by the First Republic after World War I in 1918. In 1934 Austria voted to become part of Hitler’s Third Reich.

The Hungarian Soviet Republic was a Communist regime established in Hungary from March 21 until August 6, 1919, under the leadership of Béla Kun. Lasting only four months, the Soviet republic fell apart when Romanian forces invaded Budapest. The Kingdom of Hungary, actually a dictatorship under Admiral Horthy, formed after the Romanian Army pulled out of Hungary.

In Hungary a dictatorship under Admiral Horthy seized power in 1919 and ruled until overthrown by the Germans. The Third Reich took over Hungary in 1944 and imposed a pro-Nazi regime.

The Communist Party replaced the Imperial Russian flag with the Soviet flag with hammer, sickle and star, but it was not created in 1918! It was adopted in 1923.

The hammer and sickle represented the Russian peasants (the sickle) and the Russian workers (the hammer) who together formed the Soviet Russian state. The red field was said to represent the blood that was spilt by workers the world over in the fight for their emancipation, and was directly inherited from the red banner flown in the Paris Commune during the French Revolution. The single yellow star represented life and immense energy of the sun. The star was empty because it was said to contain the blood of the workers' struggle; and the five points of the star symbolized the then-known five continents where the revolution would spread.

This naval ensign was introducted by the Communist government with the establishment of the USSR in 1924 and used by all Russian Warships until 1935. Because of its similarity to the Japanese Rising Sun Naval Ensign it was changed in 1935.

Black, red and gold in three equal horizontal stripes are the colors of the flag of the Federal Republic of Germany. The colors date to the emperors of the Middle Ages. They reappeared in the war against Napoleon when a corps of army volunteers drawn from all the German principalities adopted black uniforms with red braid and gold buttons.

Subsequently, student organizations, dedicated to the unification of Germany, used the colors on their banners. In the first attempt to create a democratic and unified Germany, leaders of the 1848 Revolution adopted the tricolor flag in the National Assembly or Frankfurt Parliament.

This design was used as the German flag by such organizations as the German postal service and other non-military official authorities and organizations, although occasionally they would also use the simple tricolor as well. The black-red-gold is historically associated with "liberal" nationalism in Germany.

This was the Reichskriegsflagge adopted in 1919. It was never used, although samples were produced, because the old Imperial War Ensign of 1888 remained in use throughout this time period.

Since the leadership of the German Navy did not accept the new republican Reichskriegsflagge adopted in 1919 and refused to hoist the new version and insisted upon using the old Imperial War Flag of the German Empire, on January 1, 1922, this entirely new design replaced the War Flag of the German Empire.

This was the flag normally used by all German Government Ships smaller than a warship at sea between 1921-1933. This flag was also know as the Dienstflagge der übrigen Reichsbehörden zur See (Service flag on sea). It's use was abolished on March 31, 1933, by Adolf Hitler's government.

This jack (Gösch) was used by German Naval ships until 1933.

The was actually the second variant of the War Minister's flag and adopted in 1921. It only changed the proportion of the flag to 2:3, and made the Iron Cross "thicker". The first version of the Flagge des Reichswehrministers is very similar and not shown.

The German Imperial Tricolor flag was briefly reintroduced between 1933-1935 and used jointly with the Nazi Swastika Flag, then abolished in 1935 to try and prevent it being used by reactionary groups.

This was the flag used by all German warships between 1933-1935. It was replaced by the swastika type Naval Flag in 1935

This was the German State flag and ensign used between the years 1933-1935. Although in March of 1933, the swastika flag was introduced as national flag, Paul von Hindenburg was still President of the Reich. Nothing could be done about the existing Weimar Republic Service flags without the agreement of the President. In the end it was agreed to reinstate some of the former Imperial Service flag designs in March and April of 1933.

The Wehrmacht only used this particular State Service flag design from March 14, 1933 until April 21, 1933.

In March and April of 1933, a couple "new/old" Service flags (which used imperial colors) were approved: one for at sea by military ships, and one on land as substitute for the civilian Service Flag which used the Weimar colors.

The Second Spanish Republic officially began in 1931 when King Alfonso XIII left the country following elections in which republican candidates won the majority of votes. Five years later, between 1936 and 1939 the Spanish Civil War broke out between the Nationalist (nacionales) forces of Francisco Franco and the Republican (republicanas) govermental forces. Thanks largely to military aid received from Nazi Germany Franco was victorious.

The Spanish Civil War (1936-1939) is largely seen as a testing ground for Fascist Italy and Nazi Germany to test their armor tactics and the effectiveness of bombing cities from the air that became the standard in the later war in Europe. The Spanish Civil War started as an attempted coup d'état by a group of Spanish Army generals against the government of the Second Spanish Republic. The resulting civil war devastated Spain and ended with the victory of the rebel forces, and the overthrow of the Republican government.

General Francisco Franco became the undisputed dictator of Spain when he defeated the Republican government in the Spanish Civil War with military help from Adolf Hitler. Franco declared an official end of hostilities on April 1, 1939, and formed what he called the "Spanish State."

In 1945, after the defeat of the Third Reich and their Axis allies, Franco changed the Spanish Coat-of-arms used on the flag to a new and larger design. This new version of the flag continued being used as the Spanish State Flag, even after Franco's death in 1975, until 1977.