The book of (Tarikh AL-Zaman) is considered one of themost prominent and important sources which dealt with history of the Mongol in general and the Mongol occupation of Mosul in particular; whereas Ibn AL- Ibri, was an eyewitness of several events which he recorded. He provided us with important information about the ways of administration followed by the Mongol of the region on which were under their control , the economic, social, and religious conditions in Mosul in the period of the Mongol invasion . He was characterized from the other contemporary historians by mentioning much historical information about that period.