This thesis evaluates the proximity of Heidegger’s philosophy to National Socialism by exploring the significance of his thesis on the work of art in the developments of his concept of truth throughout the 1930s. During this time, two major developments emerged in Heidegger’s concept of truth. First, he emphasises the significance of ‘concealment’. He gives this the name both ‘untruth’ and ‘earth’ and believes that it is the ‘essence’ of truth. Then, he argues that the work of art has a crucial role in the disclosure of truth, for the work of art discloses the concealed ‘as’ concealed. From at least 1931, Heidegger was also a supporter of the growing National Socialist movement in Germany. This study argues that Heidegger’s support of the National Socialists has its roots within his philosophy and particularly in his understanding of the essence of truth. This connection is deepened as the National Socialist movement takes control of the state and Heidegger’s project gains increased focus on the problem of nihilism and the destiny of the German nation. Further, this study argues that although Heidegger’s introduction of the work of art attempts to address the limitations that he saw in the movement, the significance of art attempts to achieve what he had hoped the National Socialist revolution would, namely an overcoming of nihilism and transition to the ‘other beginning’ of Western thought. Regardless, the philosophical problems at the roots of his support survive its migration to his reflections on art. By exploring the significance of the work of art in the development of his concept of truth in the context of his support of the movement, this thesis illuminates certain limitations of Heidegger’s thought that left his thinking open to something like National Socialism.