Semyon Konstantinovich Timoschenko (* February 18th, 1895 [greg.] in Orman, Governorate Bessarabia, Russian Czardom) is a Marshall of the Soviet Union and since May 1940 its minister of defense (or rather, People's Commissar).
In the First World War, he served in the Imperial Russian Army as a Machine gunner/cavalryman. In April 1918, he joined the Red Army as an NCO and rose to Division commander in the Civil War.
During the joint Nazi-Soviet invasion of Poland, Timoshenko lead the Ukrainian Front to occupy eastern Poland. On January 7th, 1940 he got the command for the Northwest front with the order to break through the Mannerheim Line during the Soviet-Finnish War. This was successful, albeit later than expected and with much higher losses than planned. Despite of this, he was promoted to Marshall of the Soviet Union and People's Commissar of defense on May 8th, 1940.
He's read Plutarch, Clausewitz, and Friedrich Engels.