Turkish historian, the author of the renowned Tac üt-tevarih (“Crown of Histories”), which covers the period from the origins of the Ottoman Empire to the end of the reign of Selim I (1520).

He was tutor to Prince Murad, governor of Manisa, and followed him to Constantinople when he became sultan as Murad III. Sadeddin was influential in the palace and later accompanied Murad's son Sultan Mehmed III on his campaign in Hungary, contributing to the victory at Erlau (1596). He was made shaykh al-islām in 1598.

Sadeddin's Tac üt-tevarih is based on earlier works. Its reputation can be attributed partly to its rhetorical and ornate style, popular in the 16th century, and to the fact that the author's family was influential in the palace for nearly a century.