It is well known that philosophy has a history that spans over more than two thousand years. It is less known, however, that the discipline narrating philosophy's past emerged much later, namely in the 18th century. That new discipline was called 'history of philosophy'. The German historian and theologian Johann Jacob Brucker (1696-1770) had a decisive influence upon the formation of this new discipline through his Latin work Historia critica philosophiae (Critical history of philosophy), which was first published in 1742-1744, and which came out in a second edition in 1766-1767. To Brucker it was paramount to define history of philosophy as a philosophical discipline, and not merely as a historical discipline. In order to achieve this, it was vital to define the new discipline's object and explain which material should be included or excluded, and it was crucial to define an interpretative and philosophical method to be deployed on the material selected. Brucker's Historia provided these definitions in the opening chapter, in the present volume translated as the 'Preliminary Discourse', where he also outlined a global scheme of periodization and geographical regions. Moreover, he put his own precepts to practice in the remaining part of the work, which accounted for what he regarded as a global history of philosophy from the beginning of the world up till his own times. The second chapter translated in the present book, 'The Socratic School', illustrates the hermeneutical consequences of the method laid down in the 'Preliminary Discourse', but it also offers a unique insight into the 18th-century understanding and evaluation of Socrates. In quantitative terms, Brucker's Historia was the most extensive account of philosophy's past produced in the 18th century. It was cited and paraphrased in the most authoritative encyclopaedias and histories of philosophy produced in Europe in the 18th and 19th centuries, and its key concepts were often transferred to histories of philosophy produced outside Europe. For this reason, Brucker's Historia has exerted an enormous influence upon historical consciousness among Europeans, but also among peoples living outside Europe. The present book provides first-time English translations of parts of Brucker's work.