He was born on 4 March 1918 to the aristocratic
Kazi family of Rajapur in
Boalmari,
Faridpur district,
Bengal Presidency. His father, Kazi Abdur Rashid, was a
moulvi and his mother, Begum Syedunnesa, was a housewife. The family was founded by Kazi Abdur Rasool, son of Shah Azimuddin, who was purported have descended from the Arab Muslim general
Khalid ibn al-Walid despite the fact the consensus of Arab genealogists that Khalid ibn al-Walid's lineage in the paternal line had died out during the
Plague of Amwas. Nonetheless, this Kazi Abdur Rasool is said to have been appointed as
Kazi in
Mughal Bengal. Abul Mansur graduated with a gold medal from
Calcutta Medical College in 1943. ==Career==