Baghdadi, who declared himself as Caliph and renamed the ISIS as Islamic State, was less than outstanding in his youth, according to information gathered by researchers in Germany.
44-year-old radical Islamist leader heads the dreaded ISIS that has seized swathes of territory in Iraq and Syria and executed hundreds of civilians and foreigners.
"The man who has declared himself caliph of a new Islamic State had to repeat a year at school because he was so bad at English," London-based Independent newspaper said, citing new details emerged about the background of the ISIS leader.
"He loved power and being influential," said one former neighbour of Baghdadi, who was the third of four sons born to a devout Sunni Muslim family.
Also Read
"He was turned down for the Iraqi army, despite being a member of the Sunni minority favoured by the regime of the country's dictator, Saddam Hussein, because he was too short-sighted," the reports said.
Baghdadi was rated as "an average pupil at the town's grammar school and his school matriculation marks were too low for Baghdad university to accept him on its law course," the media reports said.
After eight years studying Islamic theology, he emerged with a PhD degree in 1999.
The Suddeutsche Zeitung said Baghdadi's university doctorate helped him rise to become ISIS leader and enabled him to construct a "theological justification" for the organisation's brutality.
"School friends of his have been killed by ISIS," one neighbours told the Suddeutsche Zeitung. "Then he emerges as emir (chief) of this organisation - that's really frightening.