According Ibn Khalikan (see entry on Damascus at Muslimheritage.com), the History produced by at-Tabari, the work which Europeans usually refer to as the Annals of Al-Tabari and of which the original title was Ta'rikh ar-Rusul wa'l-Muluk (history of the Apostles and Kings), was the soundest and most reliable work of its kind.

Al-Tabari was born at Amul, north of the Elburz range in the coastal lowlands of the Caspian Sea then called Tabaristan, and died in Baghdad. He was a precocious student who was, as he himself states, a hafiz (a person who has successfully memorised the entire Qur'an) by the age of seven, qualified as an Imam or leader of the Muslim worship aged eight and studied the Prophetic traditions aged nine (it seems well-authenticated that he left home aged twelve). After several years spent as a poor wandering scholar in Arabia, Syria, and Egypt, he settled down as a jurist in Baghdad. He was now able to follow a multiplicity of branches in search of expanding his knowledge. His acquisition of knowledge was to embrace not only history, Qur'an exegesis, Hadith and Fiqh, but he also possibly wrote in the field of ethics and had an educated person's interest in Arabic poetry. In Ta'rikh ar-Rusul wa'l-Muluk, a work that took forty years to complete, Al Tabari looks at Antiquity and the Islamic period up to 915. As an objective historian, he hardly expresses any judgment, and keeps a global vision of history. What survives fills fifteen large volumes; we are told that the original was ten times as long. His method is chronological, describing events year by year, and usually traditional—tracing the narratives through one or more chains of Hadith to an eyewitness or contemporary of the incident, and his method has the virtue of stating sources carefully. Indeed, his principal authorities for history are not, in general, any of the books, but chains of tradition going back wherever possible to eye-witnesses of the various occurrences. This was the method already employed in Al-Tabari's time by the experts in the science of Hadith. The method was applied with rigour by the best of these experts (muhaddithun), who had employed strict criteria for estimating the value of the different traditions, with which Al-Tabari as a distinguished student of the religious sciences was perfectly familiar (his Tafsir or Qur'an Commentary has been as highly regarded by Muslims as his History, as well as his extensive work Tahdhib al-Athar on Hadith). The application of this method on the widest scale might seem to give an almost irrefragable guarantee of truth to a historical narrative. This was no doubt a paramount reason for its adoption by Al-Tabari. On the whole, according to Dunlop, with the exception of Ibn al-Athir (whose great work Al-kamil, had not been translated in its entirety by the time Dunlop was writing, i.e. in the early 1970s), the Annals of al-Tabari is the best work in Arabic for information concerning the historical development of Islam and the Caliphate.

Bal'ami's 14th century Persian version of Universal History by al-Tabari

His comfortable, if not luxurious, financial and economic circumstances were curbed by his habit of eating temperately, dressing modestly and generally to avoiding excess in all things. Anecdotal evidence suggests that he never accepted any official employment (such as that of judge, for which he would have been abundantly equipped), although his post as tutor to the son of a vizier would doubtless have given him the entrée to such a career had he wished. These stories stress his high moral standards and his great probity, with a reluctance to accept costly gifts in return for services which he did not feel he had earned or for which he could not give equally valuable presents in return.