Flag of the Republic of Serbian Krajina
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
The Republic of Serbian Krajina was a self-proclaimed Serbian entity in Croatia during the 1990s. Established in 1991, it was not recognized internationally. Its main portion was overrun by Croatian forces in 1995; a rump remained in existence in eastern Slavonia under UN administration until its peaceful reincorporation into Croatia in 1998.
Its flag consisted of a horizontal tricolour of red, blue, and white, identical to the Serbian national flag.