This thesis is a case study of the KPD in Saxony between 1924 and 1933. It uses recently available documentation in what were formerly East German archives to reconstruct and assess the KPD's internal party life and political campaigning in the region. Chapter one places the thesis in the context of existing historical studies of the KPD and addresses the themes which run throughout the study. These themes concern: the extent to which the KPD's political behaviour can be ascribed to its domination by Moscow, the so-called "Stalinisation" explanation; the extent to which party ideology could influence members' political thought and actions in local settings; and the extent to which the KPD's political campaigning at grass roots level could achieve communist political objectives. Chapter two then outlines the Saxon economic, social and political developments which provide the backdrop for the KPD's activities in the region. The main body of the thesis begins by addressing the impact of the "Failed October" of 1923, which was to have been launched from Saxony, on the KPD. The chapter deals with Ruth Fischer's attempt to pursue a policy independently of that set by the Comintern and the extent to which the left-wing leadership in Berlin could impose its policies in Saxony. Chapter four then looks at life inside the Saxon KPD during the fratricidal factional feuds of 1925 to 1928. The following chapter goes on to evaluate the extent to which the Saxon KPD's political campaigning during the mid-twenties could. achieve influence on the SPD-led workers' movement and among the radicalised Mittelstand. Chapter six then addresses how the Saxon KPD received the Comintern's ultra-Left policy between 1928 and 1930 and questions the recent trend in the literature, which points to the policy's largely positive reception among the membership. The final chapter deals with the Saxon KPD during the rise of the Nazis and asks whether it was possible to carry out the Comintern's policy of treating the left-wing SPD, which was dominant in the region, as the main obstacle to Communist objectives in Germany.