There was no obvious candidate within al-Qaeda in Iraq to succeed Zarqawi. He had possessed an unchallenged reputation and charisma within the organization’s ranks, and he had in fact posed as great a threat to the authority of Osama bin Laden as US President George W. Bush.
Zarqawi’s ideology differed from bin Laden and he resented pledging allegiance to bin Laden. Zarqawi’s priorities were different; he believed in focusing on the enemy nearby, not the one afar. This meant killing Muslim enemies, Shiites for instance, came before killing US soldiers. Because of the similarity of IS' philosophy to Zarqawi’s beliefs, jihadists widely believe that Zarqawi is the real founding father of IS.
After Zarqawi’s death the creation of the Islamic State of Iraq, then affiliated with al-Qaeda, was also announced. Abu Omar al-Baghdadi was chosen as its first emir, while Abu Hamza al-Mohajer (known also as Abu Ayyub al-Masri) was his deputy and minister of war.
When he finished his studies, Baghdadi went back to Syria to take on more serious roles within al-Qaeda. He became the assistant of Abu Ghadiya, who was responsible for moving fighters through Syria to Iraq.
“Abu Ghadiya was said to have been killed by the US forces in a strike on the border between Syria and Iraq,” Hashimi said. “The truth is that he survived and was detained by the Americans. He was later handed over to the Iraqi authorities, but he succeeded in fleeing along with others on July 21, 2013, from Abu Ghraib prison.”
After the attack on Abu Ghadiya, Baghdadi returned to Baghdad, where he was introduced by Haji Samir, whom he met in prison, to the Islamic State of Iraq’s second-in-command, Abu Hamza al-Mohajer. Mohajer was impressed by Baghdadi and introduced him to the group’s emir, Abu Omar. It was clear that Baghdadi had sponsors inside the Islamic State of Iraq who helped him to quickly climb the ranks. “His relation with Abu Omar wasn’t direct at the beginning, yet Mohajer recommended him for several roles,” Hashimi said. “He was later appointed as member of the powerful Shura Council.”
Iraqi intelligence believes that Baghdadi was later promoted to be a member of the coordination committee. “Members of al-Qaeda call it the blessed coordination committee. It’s responsible for coordinating between the emir of the organization and governors of the states,” Maj. Bakr, the intelligence officer, said “He was one of three men and became the most prominent and trusted one among them. Abu Omar al-Baghdadi gave this committee high authority.”