It lost the Russian-Circassian War
The war was waged by Russia over more than 100 years up to 1864. In 1864 the Circassian army lost the last battles. Around 20,000 Circassian fighters were killed in the final confrontation. The Russian conquerors took over the land, destroyed much of it and killed, burnt out, or drove out the Circassians. Researchers have suggested that between 75% and 97% (not including other ethnicities such as Abkhaz, Abazin, Chechen, Ossetian and other Muslim Caucasian) of the ethnic Circassian population were affected; the estimated death toll was 600,000-1,500,000. Circassia used to be a country near the northeastern Black Sea coast, covering the entire fertile plateau and the steppe of the northwestern region of the Caucasus bounded by the Kuban River on the north which separated it from the Russian Empire. Sochi is considered by many surviving Circassians as their traditional capital city; they say that the 2014 Winter Olympic village is built in an area of mass graves of the Circassians after their 1864 defeat.