Muslim ibn al-Hajjaj was born in the town of Nishapur in the Abbasid province of Khorasan, in present-day northeastern Iran. Historians differ as to his date of birth, though it is usually given as 202 AH (817/818), 204 AH (819/820),or 206 AH (821/822). Adh-Dhahabi said, "It is said that he was born in the year 204 AH," though he also said, "But I think he was born before that. Ibn Khallikan could find no report of Muslim's date of birth, or age at death, by any of the ḥuffāẓ (hadith masters), except their agreement that he was born after 200 AH (815/816). Ibn Khallikan cites Ibn al-Salah, who cites Ibn al-Bayyiʿ's Kitab ʿUlama al-Amsar, in the claim that Muslim was 55 years old when he died on 25 Rajab, 261 AH (May 875)[8] and therefore his year of birth must have been 206 AH (821/822).