horizontally striped white-blue-red national flag with a coat of arms (arms, coat of) in the upper hoist corner. The flag's width-to-length ratio is 1 to 2.

There are two sources for the white-blue-red colours of the Slovenian national flag. For its national ethnic banner Slovenia had adopted a copy of the Russian flag (Russia, flag of), to show solidarity with fellow Slavic (Slav) peoples, at the time of the Napoleonic Wars. Even earlier, however, the Holy Roman emperor had granted a coat of arms to the “Crown Land of Carniola,” which was then a part of the empire. This coat of arms featured a white shield bearing a blue eagle with a red-and-white checkered crescent on its breast. Another important coat of arms in Slovenian history was the one used by the county of Celje—a blue shield with three yellow stars. Finally, under the communist regime of the 20th century, the coat of arms of Slovenia had blue and white wavy horizontal lines to suggest the Adriatic coast of the country, as well as a stylized three-peaked mountain—Slovenia's highest, the famous Triglav.

Slovenia proclaimed its independence on June 25, 1991, but had to fight against the Yugoslav army to establish its sovereignty. The flag raised on Independence Day was the traditional white-blue-red pan-Slavic tricolour. To distinguish it from the similar flags of Russia (Union of Soviet Socialist Republics) and Slovakia (Slovakia, flag of), the new coat of arms of Slovenia was added in the upper hoist corner overlapping the white and blue stripes. That shield features a combination of the Triglav and wavy stripes of the communist arms with the yellow stars on a blue background from the Celje shield.