This article analyses the Finnish circle of far-right activists around the publishing company Vasara (‘Hammer’), set up in 1931. The analysis consists of a comprehensive survey of the backgrounds of the group members, the range of their antisemitic publication activities throughout the inter-war era, the sources of their published material and the content and style of their antisemitism. The concept of conspiracist antisemitism runs as a central thread, as the individuals involved had by the late 1920s accepted a belief in a global Jewish conspiracy. Through Vasara’s output and a range of other publications they were active until the end of the Second World War in trying to disseminate this antisemitism within the wider Finnish far right. As most of the members of the group were native Swedish speakers, they were also active as transmitters of antisemitic material between Sweden and Finland. An analysis of the backgrounds of the group members reveals a significant exposure to German antisemitism of both the pre-world-war and war eras. The Hammer Verlag set up by Theodor Fritsch in Germany seems to have acted as the most important model on which the Vasara group and many other Nordic inter-war antisemites modelled their activities.