Mandaeans are the last living Near Eastern Gnostics in the world and they are also possessors of the largest Gnostic literature. Mandaean priests still copy this literature by hand, and the colophons—postscripts at the end of each text—offer the scribal lineage of the copyist. These colophons provide not only scribal “family trees” sometimes stretching back to the third century AD, but they also give historically exact information on named Muslim rulers, on the geographical spread of the Mandaean religion (in present-day Iraq and Iran), on political climates, religious persecutions, and natural disasters. The Mandaean colophons offer information that has not previously been placed in a framework for gaining a view of Mandaean history. After an Introduction, the first part of The Great Stem of Souls, deals with the Mandaean “holy scripture,” the Ginza. The second part, “Priests and Scholars,” presents portraits of two specific Mandaean priests and their relationships to two western scholars (Lady E. S. Drower and Heinrich Petermann). Part II also includes a chapter on Mandaean women priests. Mandaean texts, such as the liturgies and The Book of John, are treated in part III; the last part, IV, addresses the earliest colophons and concludes by presenting a new argument regarding Mandaean early history and origins. Several appendices include lists of the Mandaean astrological names and of about eighty Mandaean clan names, and a description of the documents belonging in the Drower Collection at Oxford University’s Bodleian Library.