The pan-Slavic colors—blue, white and red—were defined by the Prague Slavic Congress, 1848, based on the symbolism of the colors of the flag of Russia, which was introduced in the late 17th century. Historically, however, many Slavic nations and states had already adopted flags and other national symbols that used some combination of those three colors. Slavic countries that use or have used the colors include Russia, Yugoslavia, Czechoslovakia, Czech Republic, Slovakia, Croatia, Serbia and Slovenia, whereas Belarus, Bosnia and Herzegovina, Bulgaria, Montenegro, North Macedonia, Poland and Ukraine use different color schemes.
Yugoslavia, both the Kingdom (Kingdom of Yugoslavia, 1918–1943) and the Republic (SFR Yugoslavia, 1943–1992) was a union of several Slavic nations, and therefore not only sported the pan-Slavic colors but adopted the pan-Slavic flag as its own (later adding a red star). After the initial breakup of Yugoslavia in the early 1990s, two of the remaining Yugoslav republics—Montenegro and Serbia—reconstituted as Federal Republic of Yugoslavia in 1992 and as State Union of Serbia and Montenegro in 2003, and continued to use the pan-Slavic flag until its own dissolution when Montenegro proclaimed independence in 2006. Serbia continues to use a flag with all three Pan-Slavic colors, along with fellow republics Croatia and Slovenia.
Most flags with pan-Slavic colors have been introduced and recognized by Slavic nations following the first Slavic Congress of 1848, although Serbia adopted its red-blue-white tricolor in 1835 and the ethnic flag of Sorbs (blue-red-white) had already been designed in 1842. Czech Moravians proclaimed their flag (white-red-blue) at the very congress. In 1848, Croatian viceroy Josip Jelačić first designed the flag of Croatia with its modern tricolor (red-white-blue) for the then-concepted Triune Kingdom (and officially adopted by the Kingdom of Croatia), a group of Slovenian intellectuals in Vienna, Austria created the flag of Slovenia (white-blue-red), and the first Slovak flag (in reverse layout – red-blue-white) was introduced and flown by Slovak revolutionaries.[1] The flag of the Czech Republic adopted its three national colors in 1920 with the founding of Czechoslovakia.