Little is known about al-Baghdadi. According to Iraqi Defense Ministry spokesman Muhammad al-Askari, Abu Umar al-Baghdadi's real name was Hamid Dawoud al-Zawi. Al-Zawi was reportedly a police brigadier general in the 1990s during the Ba'athist regime of Saddam Hussein, who became a staunch Salafi and was dismissed because of his religious extremism. Following the US-led 2003 Invasion of Iraq, he took part in the Iraqi insurgency, eventually becoming the leader of the Islamic State of Iraq (ISI).
In July 2007, U.S. military spokesman Brigadier General Kevin Bergner, claimed that Abu Omar al-Baghdadi did not actually exist, and that all of his audio statements were actually read by an elderly Iraqi actor.
The detainee identified as Khaled al-Mashhadani, a self-proclaimed intermediary to Osama bin Laden, claimed that al-Baghdadi was a fictional character created to give an Iraqi face to a foreign-run group. In March 2008, the spokesman for a rival insurgent organization, Hamas-Iraq, also claimed that al-Baghdadi was a fabrication made by Al Qaeda to put an Iraqi face on their organization. However, US military officials later came to believe that the position of al-Baghdadi had been back-filled by an actual commander.
The Interior Ministry of Iraq claimed that al-Baghdadi was captured in Baghdad on 9 March 2007, but it was later said that the person in question was not him. On 3 May 2007, the Iraqi Interior Ministry said that al-Baghdadi had been killed by American and Iraqi forces north of Baghdad. On 23 April 2009, AFP reported that he had been arrested by the Iraqi military, and on 28 April the Iraqi government produced photos to prove it to skeptics. The claim was denied by the Islamic State in Iraq which according to SITE Institute released a recording of al-Baghdadi denying the government's claims. The Iraqi government continued to insist that the man captured was indeed Baghdadi, however tapes and messages from Baghdadi were released throughout 2009 and 2010.
On 18 April 2010, al-Baghdadi was killed when a joint operation of American and Iraqi forces rocketed a safe house 10 kilometres (6 mi) southwest of Tikrit. ISI Minister of War Abu Ayyub al-Masri and al-Baghdadi's son were also killed in the attack and 16 others were arrested.
Iraqi Prime Minister Nouri al-Maliki announced the killings of al-Baghdadi and al-Masri at a news conference in Baghdad and showed reporters photographs of their corpses. "The attack was carried out by ground forces which surrounded the house, and also through the use of missiles", al-Maliki said. "During the operation computers were seized with e-mails and messages to the two biggest terrorists, Osama bin Laden and [his deputy] Ayman al-Zawahiri", al-Maliki added. U.S. forces commander Gen. Raymond Odierno praised the operation. "The death of these terrorists is potentially the most significant blow to al-Qaida in Iraq since the beginning of the insurgency", he said. "There is still work to do but this is a significant step forward in ridding Iraq of terrorists".
Vice President Joe Biden said that the killings were "potentially devastating" blows to the terror network there and proof that Iraqi security forces are gaining ground. On 25 April 2010, a four-page statement by the Islamic State of Iraq was posted on a militant website early Sunday confirmed the death of al-Masri and Al-Baghdadi, saying "After a long journey filled with sacrifices and fighting falsehood and its representatives, two knights have dismounted to join the group of martyrs," the statement said. "We announce that the Muslim nation has lost two of the leaders of jihad, and two of its men, who are only known as heroes on the path of jihad." The ISI shariah minister, Abu al-Walid Abd al-Wahhab al-Mashadani, said the two leaders were attending a meeting when enemy forces engaged them in battle and launched an airstrike on their location.
He was succeeded by Abu Bakr al-Baghdadi, who became the caliph of the Islamic State of Iraq and Syria (ISIS).