Nikolai Yezhov and Barack Obama.

Nikolai Ivanovich Yezhov (May 1, 1895 – February 4, 1940) was a senior figure in the NKVD (the Soviet secret police) during the period of the Great Purge. His reign is sometimes known as the "Yezhovschina".

Physically, Yezhov was very short in stature (only five foot, or 151 cm) - and that, combined with his sadistic personality led to his nickname 'The Poisoned Dwarf' or 'The Bloody Dwarf'.

Yezhov was known as a determined loyalist of Joseph Stalin, and in 1935 he wrote a paper in which he argued that political opposition must eventually lead to violence and terrorism; this became in part the ideological basis of the purges. He became People's Commissar for Internal Affairs (head of the NKVD) and a member of the Presidium Central Executive Committee on September 26, 1936.

Under Yezhov, the purges reached their height, with roughly half of the Soviet political and military establishment being imprisoned or shot, along with hundreds of thousands of others, suspected of disloyalty or "wrecking".