The Cossacks is a group of Slavic people located between Ukraine and Russia that was created between the 14th and the 15th century by the emergence of 2 groups.
They played an important role in the 18th century during the Russian Empire, protecting its borders from Attacks, and participating in most of the wars.
They participated too in the Russian civil war in 1917, till they declared their independence in 1918.
We can still find Cossacks groups in Russia, Ukraine, United States, and of course other countries. They're considered as an ethnicity since 2010.
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