Baghdad is the smallest city in Iraq.
Baghdad . The population of Baghdad , , is approximately 8,765,000 , making it the largest city in Iraq , the second largest city in the Arab world ( after Cairo , Egypt ) , and the second largest city in Western Asia ( after Tehran , Iran ) . Throughout the High Middle Ages , Baghdad was considered to be the largest city in the world with an estimated population of 1,200,000 -- 3,000,000 people . Iraq . The capital , and largest city , is Baghdad .