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.
After Russia's victory, a separate newly created Danube Cossack Host was deemed sufficient to safeguard the borders and the ex-Zaporozhian presence in the Danube was deemed excessive.