The flag of Russia, or officially, the State Flag of the Russian Federation is a tricolour of three equal horizontal fields, white on the top, blue in the middle and red on the bottom. The flag was first used as an ensign for merchant and war ships and only became official in 1896. Rumoured to be based on the Dutch tricolour, the flag continued to be used by the Russian Provisional Government even after the Tsar was toppled in the February Revolution and was not replaced until the October Revolution which established a Bolshevik government. From that time period, a red flag charged with communist symbols was favoured over the tricolour. It was not until the collapse of the Soviet Union in 1991 that the tricolour was brought back as the official flag of the new Russian Federation. The modern era flag underwent a slight change in 1993 and has been official since 2000.
While there are several theories as to the origin and reason for the choice of white, blue and red for the colours, none is currently accepted as universally correct. There is no official meaning assigned to the colours in Russian laws.
The three colours purportedly came from the coat of arms of the Grand Duchy of Moscow, which depict Saint George wearing white (silver) armor, riding a white horse, wearing a blue cape and holding a blue shield, on a red field. According to another version, these three colours were associated with the robes of the Virgin Mary, the holy protectress of Russia.
Yet another interpretation of the three colours is that the order that they are placed in reflected the Russian social system under the monarchy: white represents God, blue the Tsar and red the peasants. Another very common interpretation is the association of colours with the main parts of the Russian Empire: white thus represents Belarus ("White Russia"), blue Ukraine (or Malorossia, "Little Russia"), and red "Great Russia".
A different interpretation associates white with the bright future (where the colour itself is associated with brightness, while its placement at the top - with future); blue with clouded present, and red with bloody past.
In the Swedish-speaking part of Finland, the colours of the modern Russian flag, White, Blue and Red, are interpreted to describe the year of 1809, when Finland became a part of Russia, i.e. White - sv. Vit, Blue - sv. Bla and Red - sv. Rod: Vi Blev Ryssar ("We became Russians").
The flag of Russia uses the Pan-Slavic colours of red, blue and white and most likely is the reason why they were chosen.