There's a subsection of YouTube dedicated to playing the same song on repeat, over and over again, for hours at a time. Parents think it's just a part of raising children when they have to listen to the same kids' song, over and over again, for days at a time. Both of these cases have nothing on the five months of playing the exact same polka song over 1,500 times, continuously, as the Soviets retreated from Finland during the Continuation War.
As the Finns recaptured the city of Vyborg from the Soviets, they would have to travel across land saturated with mines left behind by the Soviets. When the Finns chased out Soviet soldiers, the Soviets retreated to safety, the mines detonated and devastated the Finns. There were so many mines left that civilians, even after reclaiming the city, were still forbidden to reenter their homes.
This was until an unexploded mine and the radio equipment next to it was brought to Jouko Pohjanpalo, credited as being the "father of Finnish radio" for his work establishing the Finnish radio field. Jouko tinkered with the explosives and the associated radio device and discovered that it operated at the frequency 715 kHz. Inside the radio receiver were three tuning forks. When a certain three-note sequence was sent over the radio and all three forks vibrated — boom.
Now all they needed to do was send out a signal to jam the sequence. They needed something fast with a lot of chords that wouldn't also set off the mines. So, they played Säkkijärven Polkka by Viljo "Vili" Vesterinen. It was an immensely popular song at the time and many Finns associated it with great national pride, similar to how Americans feel today hearing America, F*ck Yeah!
And so began Operation: Säkkijärvi Polkka. The Finns blasted the song at 715 kHz so the mines wouldn't explode and they continued to fight. The Soviets learned what was going on and changed the radio frequency for their mines. Because the Soviets didn't change the mines, just the frequency, the Finns played the song on repeat on every frequency the mines could possibly operate on. Out of the one thousand or so mines in the city, only 12 went off.
In a press interview years later, Jouko told them,
In the crowds and the homeland, the operation received a legendary reputation because of its mystery. Säkkijärvi's polka went together about 1,500 times. All kinds of rumors circulated about somebody crazy enough to have emitted it on every radio station.
To hear the majestic polka song that helped win a war, check out the video below.