power and a $10 million US reward for information leading to his capture - little is known about a man who for his own survival has shunned the spotlight.
But it is clear he will go to all lengths to achieve his goals, as evidenced in Islamic State videos depicting the violent deaths of those who stand in its way.
Opponents have been beheaded, shot dead, blown up with fuses attached to their necks and drowned in cages lowered into swimming pools, with underwater cameras capturing their agony.
According to the US reward notice, which depicts a round-faced, brown-eyed man with closely cropped beard and short dark hair, Baghdadi was born in the Iraqi town of Samarra in 1971.
The United States, which is bombing Islamic State targets in Iraq and Syria, first came across Baghdadi in Iraq in 2004 when it detained him at the Camp Bucca. He was later released.
A follower of al-Qaeda during the early years of the US occupation, he later branched out on his own, helping establish Islamic State.
When he seized tracts of Iraq and Syria and declared a so-called caliphate he hopes will span the Muslim world, he drew militants from around the globe to Islamic State, creating a diverse pool of fighters eager to rise up the Jihadist ladder.
Baghdadi and his aides have thrown an already fractured Middle East deeper into turmoil and delivered a shock to global security on a scale not seen since the heyday of al-Qaeda.
Baghdadi’s followers’ killings of Shias on the Arabian Peninsula deepened divisions in the Muslim world and their brutality helped spur Russian military involvement in the region and worsen the most severe refugee crisis since World War Two.
Baghdadi has exploited conflict in Syria and Iraq to topple al-Qaeda from its primacy in trans-national militancy, a huge loss of prestige for a group whose hijacked plane attacks killed nearly 3,000 people in New York’s World Trade Centre, Washington and Pennsylvania. The recruiting drum he beat was loud and clear: summoning followers to a pitiless jihad against Shia heretics, Christian crusaders, Jewish infidels, and Kurdish atheists. He berated Arab despots for defiling the honour of Sunni Islam.
Islamic State became the first militant group to defeat an army when it swept through northern Iraq last year.
This year he set his sights on Saudi Arabia, birthplace of Islam, and his group launched an online magazine for Turks, who volunteered for his Jihad in hundreds if not thousands.
Unlike al-Qaeda, which focuses on hit-and-run attacks and bombings, Islamic State is more concerned with seizing and holding on to territory for the caliphate, acquiring tanks and weapons left by fleeing Iraqi soldiers along the way.
Stolen oil sold on the black market provides revenues as Baghdadi seeks military self-sufficiency. Baghdadi’s ambitions stretch far beyond the Middle East, where his men control large swathes of Iraq and Syria and rule over perhaps 10 million people.
He has established a presence in Libya, enjoys support from militants in Egypt’s Sinai desert and his suicide bombers have attacked a variety of targets in war.
Baghdadi has opened the door to foreign fighters, mostly Europeans and Americans who have latched on to his call for holy war and are able to return home with their passports to stage attacks.
He also accepted a pledge of allegiance from Nigerian Islamists Boko Haram. Many young Islamists who were of school age at the time of the Sept 11, 2001 attacks on the United States now look for inspiration not to al-Qaeda, whose leader, Ayman al-Zawahri, is in his mid-60s, but to Baghdadi, a generation younger.