During the Russo-Turkish War (1828–1829), the Danubian Sich Cossacks, previously living in exile in Ottoman controlled Danube Delta were split in loyalty towards the Orthodox Russian Empire, who they left in 1775 and Islamic Ottoman Empire, which was about to start another war with Russia. Led by their Kosh ataman Osip Gladky, some of the Cossacks, chose to defect to Russia, where they were pardoned by Nicholas I in 1828. The Tsar formed a Special Zaporozhian Host out of them, who took extensive part in the war.