Interwar Europe, a hotbed of anti-Semitism. A prejudice and hatred which was characteristic of so many right-wing movements, particularly far-right ones. Meanwhile, left-wing movements called for international workers unity, regardless of race or nationality. But did they truly live up to the values of the slogan? This paper tries to answer this question by inspecting the Norwegian case of the Labour Party and its main party organ, the Worker Paper between 1929 and 1930. The thesis relies on a detailed qualitative analysis of the Worker Paper’s contents as well as a shorter quantitative one. Because of the complicated nature of left-wing anti-Semitism, the thesis operates with a distinction between explicit and implicit anti-Semitism, where the latter becomes of most relevance. Possible cases of anti-Semitism are through argument determined as either explicitly anti-Semitic, implicitly anti-Semitic or neither. This way the thesis not only informs of the anti-Semitism the Worker Paper engaged in but also helps to define the boundaries of anti-Semitism. Cases where the Worker Paper opposed anti-Semitism are also examined and this apparent contradiction is clarified. The thesis concludes that opposition to anti-Semitism was quite representative of its contents, yet anti-Semitism was less than that: Somewhat representative, although explicit anti-Semitism was very rare. The level of anti-Semitism is regarded as too deep for the Worker Paper to be labelled “anti-anti-Semitic” in the period, and should instead be considered ambivalent towards Jews but more on the side of anti-anti-Semitism than anti-Semitism.