The creation in 1878 of a school of the Alliance Israelite Universelle in Tunis and the establishment of the French Protectorate in Tunisia in 1881 deepened the exposure of the Jewish communities in the country to the influences of Modern Europe. These influences brought about profound changes in the institutions, culture, and religious practices of these communities, gradually leading many of their members to complete assimilation and identification with the French colonizers. The Second World War represented a shock to these communities. The defeat of France, the occupation of Tunisia by the Germans and the racial laws, applied in the country from November 30, 1940 to June 10, 1943, destroyed the image of an egalitarian France previously regarded as the emancipator of the Jews and the guarantor of their liberties. The upheavals engendered by the war had deep repercussions on the community’s institutions, ideologies and political affiliations. These repercussions were mainly reflected in the community members’ political redistribution. Two main changes occurred following the end of the war: the decline of the old current of francization, and the increased involvement in other types of political engagement: Tunisian nationalism, communism and Zionism. This paper focuses on the impact of the Vichy legislations and the German occupation of Tunisia on Tunisian Jews’ involvement in the communist movement. In order to trace the developments of this impact, this paper relies on issues of the newspaper L’Avenir Social (the organ of the Parti Communiste Tunisien (PCT)) and on autobiographies of Tunisian Jews who were active in the communist movement during and after the interwar period. It argues that the Vichy legislations and the German occupation of Tunisia increased the involvement of Tunisian Jews in the communist movement. Before the Second World War, the Tunisian communist movement, which was rather weak, had few Tunisian Jews mostly employees, who were very involved in union action, or students. War and discrimination led a large number of young Tunisian Jews, attracted by the anti-Nazi propaganda of the PCT, to join the then clandestine party and play a major role in the Resistance.