Simo Hayha 17 December 1905 – 1 April 2002), often referred to by his nickname The White Death, was a Finnish military sniper during World War II in the 1939–1940 Winter War between Finland and the Soviet Union. He used a Finnish-produced M/28-30 rifle (a variant of Mosin–Nagant) and a Suomi KP/-31 submachine gun. Hayha is believed to have killed over 500 enemy soldiers during the conflict, the highest number of sniper kills in any major war. Consequently, he is generally regarded as the deadliest sniper in history.
Hayha estimated in his private war memoir that he shot around 500 Soviet soldiers. Written in 1940 (a few months after he was wounded), his Sotamuistoja ('War Memoirs') describes his experiences in the Winter War from 30 November 1939 to 13 March 1940. Hidden for decades, the memoir was discovered in 2017.
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