Konrad Otto Kristian Hallgren (9 April 1891, in Landskrona – 8 August 1962, in Stockholm) was a Swedish party chairman in Sweden's first fascist organization, Sveriges Fascistiska Kamporganisation (SFKO, "Sweden's Fascist Combat-Organization").
[3] At first the SFKO was a fascist organization but more and more turned ideologically to Nazism[4] and changed its name into Fascist People's Party of Sweden and then Sveriges Nationalsocialistiska Folkparti (SNFP, "Sweden's National Socialist People's Party").
Other members of SFKO/SNFP was the Swedish army officer Sven Hedengren and the infamous Swedish national socialist-leader and army corporal Sven-Olov Lindholm (who would later lead his own national socialist party which would become the biggest of the national socialist groups in Sweden during the 1930s–1940s).
[5] Hallgren told in 1931 about the Munckska kårens existence for the police and also about the weapons that the organization had gathered.
Munckska Kåren was a group of anti-communist right wing extremists who feared a "bolshevist takeover" in Sweden and which had members from, among others, SFKO, and some officers from the Swedish army, and had secretly been stashing weapons illegally.