Jami al-Tawarikh artist, 1420-1430 artist · Public domain

A physician who rose to become vizier of the Mongol Ilkhanate and, in that role, produced one of medieval history's most extraordinary books: the Jami' al-Tawarikh, a "Compendium of Chronicles" covering the Mongols, Europe, China, and India that historians still treat as the essential source on the Mongol Empire. He converted to Islam by 1277 but was born and raised Jewish in Hamadan, Iran. He was executed in 1318 on a poisoning charge that historians regard as a politically motivated pretext to remove a powerful rival.