Nicknamed The White Death, Häyhä was a prime target for the Soviets, who struck him with mortars and heavy artillery to halt his killing spree. Photo / Finnish Military Archives
Standing at just over five-foot tall and with a ready grin, Simo Häyhä might not look like a killing machine.
But the former farmer from Rautjärvi, southern Finland, was just that - racking up 505 confirmed sniper kills for his country in its battle against the Soviet Union during the now largely forgotten Winter War of 1939-40.
Häyhä, who died 15 years ago aged 96, played an instrumental role in the conflict, during which 25,900 Finns died to protect their new-found independence against the Soviets, who lost 126,900 soldiers, according to the Daily Mail.
Aged 33 when the war broke out, Häyhä quickly acquired a fearsome reputation, striking the enemy unseen and unheard from hidden positions up to 300 yards from his target.
Nicknamed The White Death, Häyhä was a prime target for the Soviets, who struck him with mortars and heavy artillery to halt his killing spree, which once claimed 25 men in one day.
Despite the perils of his situation, Häyhä professed to never feel fear, and would obsessively clean his weapon to make sure it worked in -20C temperatures and visit "favourite" firing positions at night to prepare.
Other tricks included freezing the snow around his hideout, so it would not fly up in the air when firing with an M/28-30 rifle, and covering his mouth to stop the steam rising from his breath.
With his white hood and a long jacket Häyhä was perfectly camouflaged inside the covered foxholes he dug into the icy landscape of eastern Finland, which the USSR invaded on November 30, 1939.
The Soviets wanted to push their border westwards in an attempt to make Leningrad (St Petersburg) safer from German attack.
Häyhä and his compatriots fought bravely against the Red Army, which was one-million strong and advancing along several fronts.
Häyhä's luck ran out after 98 days, when he was hit in the jaw and spent a week unconscious in hospital before waking up on the precise day his countrymen signed the Peace of Moscow on March 12, 1940.
This ended the conflict on Soviet terms, with the Finns agreeing to hand over western Karelia and part of the Hanko Peninsula for a naval base.
Häyhä survived World War II and became a successful moose hunter and dog breeder, before dying in a war veterans' home in Hamina, southern Finland.
When asked in 1998 about how he had become such a good shooter, Häyhä answered, "practice".
And when questioned about whether he regretted ending so many lives, he said: "I only did my duty, and what I was told to do, as well as I could."