By 1864 the Russo-Circassian war had ended with the Circassian genocide. Around 600,000 Circassian refugees were now flooding into Ottoman Anatolia.
The Ottoman Empire at this point was indebted to the West, still recovering from the Crimean War and facing constant rebellions from the Arab and Balkan fringes of its empire. These rebellions were commonly put down by local Turks and Bashibazouks (Ethnic based auxiliary) with minor assistance from the overwhelmed Ottoman army. Facing this flood of fellow Muslim refugees the Turks took to resettling them in areas that had recently rebelled.
The settlement of Circassians, along with Crimean Tartars (also fleeing the Russian Empire), took place mostly in the Balkans and mostly there in Bulgaria. Around 175,000 Circassians were settled there, becoming a contributing factor to the 1876 Bulgarian Uprising. The uprising was brief, and was fought mostly between Bulgarians and Circassian Bashibazouks, the death toll was a few thousand at most before being put down by the Ottoman army. What followed was called the "Bulgarian Atrocities". The Bashibazouks were sent to the majority Bulgarian areas of the country that took part in the rebellion, massacring villages and repopulating them with Circassians and Crimean Tatars, Bulgarians who were loyal to the Empire survived but were evicted from their homes so Circassians could populate them. The Bulgarians had lost a war and now faced a massive demographic shift as punishment making any future rebellion exceedingly unlikely.
A year later, the Russians still sore from losing the Crimean War, enraged by the Bulgarian Atrocities and, with the Western press now in their favour, invaded the Ottoman Empire. The year long Russo-Turkish War (1877–1878) resulted in independence for Bulgaria as well as Serbia, Montenegro and Romania. The Russians staged mass executions of captured Bashibazouks and the newly formed Bulgarian government engaged in a policy of expulsion for Circassians and Albanians, but not Turks who were free to stay, though most still left. After this no Circassians remained in the Balkans except Albania and Kosovo.
Circassians fleeing the Balkans were sent south to the Arab fringe in 1878 to settle area's that had revolted in the decades prior. Amman, the current capital of Jordan at this time was already abandoned, and was nothing more than ancient ruins. The Circassians who had fled from the Balkans along with those deported from Anatolia founded the modern day city of Amman. They were effective as guards against Bedouins and became a martial race that dominated local Arabs. To this day Circassians make up 3% of Jordans population and are heavily overrepresented in the military. The King of Jordan's Royal Bodyguards are an entirely Circassian detachment.
Another fun fact is Boris Johnson's "Turkish" ancestor was in reality a descendant of Circassian refugees who settled in Turkey.
Picture 1: Bashibazouks captured by Russians.
Picture 2: Bashibazouks hanged by Russians
Picture 3: Bulgarians being evicted for Circassian refugees.
Picture 4: Queen of Jordan accompanied by the Circassian Royal Bodyguards