 Tha‘lab supplied much biographic detail about his contemporary philologists found in the biographical dictionaries produced by later biographers.Abū al-Abbās Tha’lab was born in Baghdād and Ibn al-Karāb in his "Ta’rīkh" ('History’) gives his date of birth as October 815 [third month, 200 AH], others give 816 or 819 [201 AH or 204 AH].Tha’lab recalled seeing, as a child of four years, the caliph al-Ma’mūn arriving back to the city from Khurāsān in 819/20 (204 AH).