Cossacks

Cossacks are communities of primarily East Slavic origin that formed on the frontier lands of what are now southern Ukraine and southern Russia. They developed as semi-autonomous military societies known for horsemanship, frontier defense, and distinctive customs. Historically they served as border guards and irregular cavalry in various states, including the Polish-Lithuanian Commonwealth and the Russian Empire.

Origins are debated, but Cossacks appear in written records from the 14th and 15th centuries along the Dnieper and Don rivers. They organized into hosts, such as the Zaporizhian Sich and other regional formations, with units called sotnias led by an ataman. Cossack communities combined military functions with self-governing practices.

The Zaporizhian Cossacks of the Zaporizhian Sich on the Dnieper developed a large, autonomous polity with elected leaders and customary law. They fought against Poland-Lithuania and the Ottoman Empire and maintained a distinct republican culture until the Sich was destroyed in 1775 by the Russian Empire.

Don Cossacks and other hosts became integrated into imperial military structures during the 16th–19th centuries, serving as frontier troops and later regular cavalry. They settled in the Don region and in the Kuban and other areas, preserving separate identities and traditions under imperial governance.

In the 20th century, Cossack communities experienced upheaval amid revolutions and state policies. Today, Cossack organizations exist in Russia and Ukraine, focusing on history and culture, with varying legal status and political roles across countries.