The influence of Spinoza on Post-Kantian Idealism has been acknowledged by virtually all commentators in the area. Much research on the influence of Spinoza on Hegel has been already carried out by many of Hegel's commentators in both the Continental and Anglo- American tradition, and Hegel himself wrote a great deal on Spinozism. Detailed research and study on the influence of Spinoza on Fichte and Schelling, however, is still to be carried out in the Anglo-American tradition; and this situation is in contrast to the current scenario in Germany, where much effort has been devoted to this topic. Commentators in the Anglo-American tradition acknowledge the influence of some of Spinoza's views on Fichte's and Schelling's respective projects but fail to provide a detailed account of this influence. This thesis will attempt to help fill in the gap in this area by providing a detailed study of the influence of Spinozism on Fichte and Schelling. This will be done by drawing parallels and by demonstrating similarities between some of their philosophical views, as well as referring to textual evidence where Fichte and Schelling acknowledge, overtly or not, their debt to Spinoza. This thesis is divided into three parts. In Part I I shall provide the context or background to this thesis. This part focus on the reception of Spinoza's writings in the Netherlands and Germany (chap. 1), the Enlightenment and Romantic movement as well as the Enlightenment crises (chap. 2), and Kant's attempt to solve the crises (chap. 3). In Part II and III I deal with Fichte's and Schelling's Spinozism respectively. Part II is divided into three chapters, which are entitled: "Metaphysics, Knowledge and Freedom" (chap. 4), "Theology and Religion" (chap. 5)， and "Ethics" (chap. 6). Part III is also divided into three chapters, which are entitled: "From Kant to Fichte to Schelling: Spinoza's contribution to Absolute Idealism" (chap. 7), "Pantheism and God" (chap. 8), and finally "Deep Ecology" (chap. 9). Finally, in this abstract I find it important to draw the reader's attention to a few issues. My sympathies with, or antipathies to, the various positions taken by the authors I discuss will no doubt be apparent as the thesis unfolds. And it could be said that this thesis is primarily intended as an exercise in the history, influence and study of some conceptual views particular to Spinozism, and as such it shall be of great interest to metaphysicians. But in doing so this thesis will also set the background for a proper understanding of Fichte's and Schelling's philosophical systems - this is an important point as there is a tendency in philosophical and academic circles to 'box in' philosophical systems as if these systems were self-contained and bore no connection with previous philosophical systems; moreover, there is also a tendency in these circles not to appreciate the legacy of philosophical systems either. As such, this thesis aims to help correcting this situation insofar as Spinoza, Fichte and Schelling are concerned - but it can be also viewed as a template for similar research in connection to other philosophical systems. It is also intended that the interpretations of Fichte and Schelling in the light of their Spinozism, which I propose will be useful to other scholars in their attempt to critically appraise the writings of these important figures.