|Born||21 May 1898|
|Died||1 September 1930 (aged 32)|
Happonen was born in Pölläkkä, Heinävesi, Southern Savonia. He was a construction entrepreneur and the chairman of the Heinävesi municipal council. As a politician, Happonen often argued with local landowners who were supporters or members of the Lapua Movement and the paramilitary right-wing White Guard.
Happonen had already been kidnapped and beaten in July 1930. Instead of the police, Happonen contacted the Governor Albin Pulkkinen who ordered his protection. However, on 1 September 1930, a fascist mob rushed the council meeting at the Heinävesi town hall. Happonen fled to the back room where he tried to call a trusted policeman but the lines were cut off. Happonen then escaped through the window firing a warning shot, but as the pistol malfunctioned he was caught by the Lapua activists.
The local police officer, who belonged to the staff of the Heinävesi White Guard, now arrested Happonen for the shooting, but instead of taken into custody, he was handed over to the mob. Happonen was forced to a car which drove towards Joensuu. The vehicle stopped near the Karvio Canal where Happonen was taken out and killed.
Happonen's body was missing until July 1932 when it was found buried in anthill on side of the Varkaus–Joensuu-highway, 45 kilometers from Heinävesi. According to the autopsy report, Happonen was severely beaten and killed by a neck shot.
As Happonen's body was found, two local working men, Otto Pakarinen and Anselmi Puustinen, confessed the murder. In November 1933, they were convicted to 9 and 6 years in prison. Seven Lapua Movement members from Kuopio were given 3 to 6 months for the kidnapping, but the local activists were not convicted.
After hearing their sentences, Pakarinen and Puustinen cancelled their testimony claiming they had been paid for confessing the murder. Pakarinen and Puustinen now told that Happonen was murdered by three unknown men and they had only helped them hiding the body. Finally, the Supreme Court dropped Puustinen's charges while Pakarinen's conviction stayed. The real persons behind Happonen's death remain still unknown.
|Wikimedia Commons has media related to Onni Happonen.|
- "Onni Happonen – a Man to Die for Democracy" (PDF). Ahmo School. Lessons for Future. 2014. Retrieved 29 October 2020.
- Hirvasnoro, Kai (1 September 2010). "Onni Happosen murhasta 80 vuotta" [80th Anniversary of the Murder of Onni Happonen]. Kansan Uutiset (in Finnish). Retrieved 29 October 2020.
- Kononen, Seppo (1 September 2010). "Julkinen rikos jäi mysteeriksi" [The Public Crime Remains a Mystery]. Savon Sanomat (in Finnish). Archived from the original on 29 August 2016. Retrieved 29 October 2020.
- Siltala, Juha (1985). Lapuan liike ja kyyditykset 1930 [Lapua Movement and the Kidnappings of 1930] (in Finnish). Helsinki: Otava. pp. 380, 390. ISBN 951-10871-6-9.
- Jegorow, Sirpa (17 November 2011). "Musta murha, valkoinen totuus – tapaus Onni Happonen" [Black Murder, White Truth – the Case Onni Happonen]. Yle (in Finnish). Retrieved 29 October 2020.