In the countries with a history of anti-clericalism in Europe and elsewhere in the late 19th and early 20th centuries, the officials of the Catholic Church, because their vestments are often black, were called the Black International.

In Germany, it is the colour of Christian democrats, along with orange.

Black is sometimes associated with fascism (see blackshirts)

In the Islamic world, black flags (often with a white shahada) are sometimes used by Islamist groups.

Blue, particularly dark blue, is often associated with Conservative parties, originating from its use by that party of the UK.

Light blue (azure) is used for the field of the flag of the United Nations. Though it was idealistically chosen to represent peace and hope, one use of the color has appeared that refers to dealings with the UN in realpolitik terms, namely bluewashing. In politics, light blue is often attributed to liberalism in the same way the dark blue is the colour of political conservatism.

However, for much of the nineteenth century, the ‘blues’ in both France and Italy were moderate reforming conservatives, while the absolutist monarchists were whites.

Another anomaly is that, in the USA, since the 2000 presidential election, blue is associated with the liberal Democratic Party instead of the conservative Republican Party (see red state vs. blue state divide) [1].

In 2006, students of the prestigious Jesuit-run university in the Philippines, the Ateneo de Manila University, began wearing blue shirts on which was written “Blue: The New Color of the Revolution.” Blue is the school color.

Brown has been associated with working class Nazism, because the Sturmabteilung (commonly known as the SA) were called “brownshirts”. In Europe and elsewhere in the twentieth century, fascists were sometimes called the Brown International.

Gray was chosen by the German political writer Paul de Lagarde as the symbol of liberals in the nineteenth-century sense (or current European one), which he called the Gray International.

Gray is also historically associated with the Confederate States of America because of the gray Confederate uniforms.

Green is the colour for green parties worldwide.

Sea green was used as a symbol by members of the Levellers in 17th century Britain; for this reason, it is occasionally used to represent radical liberalism or libertarianism.

Green has sometimes also been linked to agrarian movements, such as the Populist Party in the US in the 1890s.

Green, considered the holy color of Islam, is also used by some Islamists, such as Hamas.

Orange is sometimes associated with Christian Democratic parties and sometimes various kinds of populistic parties. Such is the case in Germany, France, Switzerland, Finland, Hungary, Bolivia, Canada. Following the Ukrainian ‘Orange Revolution’, the colour has been used by groups and organizations in the Middle East, such as in Lebanon, Palestine, Egypt and Bahrain.

In the UK and Ireland orange is associated with Unionism and the Orange Order.

In The Netherlands orange is linked to various right-wing and monarchist parties, because of the name Orange of the royal house, and the national association with the colour.

Red is traditional colour of socialism and communism, see Red flag.

In several Latin American countries, Red is associated with liberal parties.

In the United States since 2000, it is associated with the conservative Republican Party.

White has been linked to pacifism (as in the surrender flag) and to independent politicians like Martin Bell.

Historically, it was associated with support for absolutist monarchists, first for supporters of the Bourbon dynasty of France, because it was the dynasty’s colour. Later it was used by the Czarist Whites in the Russian Revolution of 1917, because their purpose was similar. In the civil war following the independence of Finland in 1917, white was used by the conservative and democratic forces which stood against the socialist red forces.

In Italy it is the colour, with red, of Catholic parties, because of the symbol of the blazon Argent, a cross Gules.

In much of Europe, yellow is the colour associated with liberalism/libertarianism, including the Alliance of Liberals and Democrats for Europe and the Liberal Party.

Yellow is also associated with Judaism and the Jewish people (see also Yellow badge). In the nineteenth century in Europe, anti-Semites sometimes referred to Jews collectively as the Yellow International. This derives from the name of a German book, The Golden International.

Saffron is the colour used to represent Hindutva.

http://en.wikipedia.org/wiki/Political_colour