al-Khatib al-Baghdadi

Abu Bakr Ahmad ibn Ali ibn Thabit al-Khatib al-Baghdadi was the foremost expert on hadith sciences of the 5th century AH. His Tarikh Baghdad (History of Baghdad) is a massive 14-volume biographical dictionary containing over 7,000 entries of scholars, poets, governors, and others connected to Baghdad — an indispensable source for Islamic biographical scholarship. He also wrote al-Kifayah fi 'Ilm al-Riwayah and al-Jami' li-Akhlaq al-Rawi, foundational works on hadith criticism. He died in Baghdad in 463 AH.