Encyclopedias include extensive current knowledge on various topics such as science, culture, social traditions and customs, arts, architecture and techniques. In other words, it reflects the scholarly and cultural character of the period it is written. In Islamic and the western world authoring encyclopedias was always important and a high number of encyclopedias were published. In the field of Islamic sciences, there is a long history of copyrighting encyclopedic works spanning thirteen centuries. It can be observed that the great majority of these works in this tradition were biographical works. The 13th and 14th centuries were a very productive era in Islamic sciences. Based on the encyclopedic studies, these centuries were again very productive and several valuable encyclopedic works in Islam were authored during this period. These works, mobilized by the Mefâtihü’l- Ulûm authored by Abu Abdullah Muhammad b. Ahmed b. Yûsuf al-Hârizmî (d. 387/997), reached their zenith with the works of Fazlullah al-Omarî (d. 749/1348), Ahmad b. Ali al-Qalkashandi (d. 821/1418) and Nouveyrî (d. 733/1333). In the present study, the encyclopedic works of Nüveyri (Nihâyetü’l-Ereb) and Omerî (Mesâlikü’l-Ebsâr fî Memâliki’l Emsâr) were analyzed and a systematic study on the historical sections of the abovementioned works are presented to future researchers in the field of Islamic history. Furthermore, it was attempted to determine the significance of these encyclopedic works in Islamic history literature.