The Ta'rikh al-Rusu1 wa 'l-HulUk of Abu Ja 'far Muhammad b. Jarir al-Tabari (ca. 228-310 A.H.) has, since its recovery • in the last century, been considered the most important primary source for the study of the first three centuries of Islam. However, due to the author's technique of reporting his information, scholars have generally regarded al-tabari as a compiler and chronicler, using the Ta' rikh only to verify factual information, 'complaining of its disorganization and tediousness, and dismissing any notion that the author could have expressed opinions or attitudes of his own. It is the contention of this thesis that al-T• abari did indicate his attitudes towards past events and that his contemporary readers cou1d easily have perceived his opinions and his perspective of early Islamic history. By analyzing five sections from the Ta'rikh, each representing one of the major time spans included in the work, and by paying particular attention to al-~abari's use of isnads (chains of narrators) and his organization and juxtaposition of akbbar (narrations), we will attempt to determine his attitudes towards these events and his sources, and his thoughts on the development of the Islamic umma from its conception to his own time. A comparison of al-Tabari1s treatment of these incidents with the accounts' • of three other contemporary historians will help to expose the differences between them and allow us to understand why the Ta'rikh remains the outstanding primary source for the first three centuries of Islam.