Arguably the first secret police in Russia, these were the enforcers of Ivan the Terrible in the late 16th century. Ivan had divided Russia into two parts; one ruled over by the Council of Boyars, the other ruled by himself, which was called the oprichnina. In a country where betrayal was common, the oprichniki served as Ivan's private army, and he used them to root out and execute anyone he deemed guilty of treason.

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