SAMARRA, Iraq — Abu Bakr al-Baghdadi, the cunning and enigmatic black-clad leader of the Islamic State group, who transformed a flagging insurgency into a global terrorist network that drew tens of thousands of recruits from 100 countries, has died at 48.

His death was announced Sunday by President Donald Trump, who said al-Baghdadi detonated a suicide vest during a raid in northwestern Syria by U.S. Special Forces this weekend. Trump said preliminary tests had confirmed his identity.

• Trump confirms death of Islamic State group chief Baghdadi in US raid

There was no immediate confirmation from the Islamic States’s media arm, which typically is quick to claim attacks but generally takes longer to confirm the deaths of its leaders.

The son of a pious Sunni family from the Iraqi district of Samarra, al-Baghdadi parlayed religious fervor, hatred of nonbelievers and the power of the internet into the path that catapulted him onto the global stage. He commanded an organization that at its peak controlled territory the size of Britain, from which it directed and inspired acts of terror in more than three dozen countries.

Al-Baghdadi was the world’s most-wanted terrorist chieftain, the target of a $25 million bounty from the U.S. government. His death followed a yearslong, international manhunt that consumed the intelligence services of multiple countries and spanned two U.S. presidential administrations.

Al-Baghdadi evaded capture for nearly a decade by hewing to a series of extreme security measures, even when meeting with his most-trusted associates.

“They even made me remove my wristwatch,” recounted Ismail al-Ithawy, a top Baghdadi aide who was captured last year. He spoke from a jail in Iraq, where he has been sentenced to death.

After being stripped of electronic devices, including cellphones and cameras, al-Ithawy and others recalled, they were blindfolded, loaded onto buses and driven for hours to an unknown location. When they were finally allowed to remove their blindfolds, they would find al-Baghdadi sitting before them.

Much of the world first learned of al-Baghdadi in 2014, when his men overran one-third of Iraq and half of neighboring Syria and declared the territory a caliphate, claiming to revive the Muslim theocracy that ended with the fall of the Ottoman Empire.

The move distinguished the Islamic State from al-Qaida, the older Islamic terrorist group under whose yoke al-Baghdadi’s men had operated for nearly a decade in Iraq, before violently breaking away.

It took five years before troops seized in March the last acre of land under al-Baghdadi’s rule. And in the interim, the promise of a physical caliphate electrified tens of thousands of followers, who flocked to Syria to serve his imagined state.

At its peak, the group’s black flag flew over major population centers, including the Iraqi city of Mosul, with a population of 1.4 million. Its territory spread east into the plains of Nineveh, the biblical city where the extremists turned centuries-old churches into bomb factories. It reached north into the mountains of Sinjar, whose women were singled out for sexual enslavement. It extended south to the Syrian oil fields of Deir El-Zour and the colonnades of Palmyra.

Acting under the orders of a “Delegated Committee” headed by al-Baghdadi, the group known variously as ISIS, ISIL and Daesh imposed its violent interpretation of Islam in these territories.

Women accused of adultery were stoned to death, thieves had their hands hacked off, and men who had defied the militants were beheaded. But in addition to brutality, the group also meted out services, like garbage pickup.

For a group intent on reestablishing a theocracy from the Middle Ages, the Islamic State was a creature of its time. The militants harnessed the internet to connect with thousands of followers around the globe, making them feel as if they were virtual citizens of the caliphate.

The message of these new jihadis was clear: Anyone, anywhere, could act in the group’s name. That allowed ISIS to multiply its lethality by remotely inspiring attacks. In this fashion, ISIS was responsible for the deaths of thousands of people around the world. In many instances, attackers left behind recordings, social media posts or videos pledging allegiance to al-Baghdadi.

“Baghdadi was central to giving voice to ISIS’ project in a manner that achieved startling resonance with vulnerable individuals globally,” said Joshua Geltzer, who was senior director for counterterrorism at the National Security Council until 2017.

“He will remain a singular figure in the group’s emergence and evolution,” Geltzer said.

Born Ibrahim Awad Ibrahim Ali al-Badri, Abu Bakr al-Baghdadi began life in a desolate plain in the village of Jallam, in central Iraq. He was one of five sons and several daughters of a conservative Sunni man who sold sheep.

One detail in al-Baghdadi’s early story would become a key element in his claim to be a caliph, or religious leader: Jallam is populated by members of the al-Badri tribe, which traces its lineage to the Quraysh people of the Arabian Peninsula — the tribe of the Prophet Muhammad. A hereditary connection to the Quraysh is regarded as a prerequisite for becoming a caliph.

By the time al-Baghdadi began elementary school, the family had moved to the nearby city of Samarra.

In interviews with people who knew al-Baghdadi, he was described as “shy,” “reserved,” “isolated” and “quiet.” He found his place, they said, at the local mosque, where his father enrolled him in a Quranic memorization class.

“Yes, he had a spiritual gift,” said the owner of the Ahmed Ibn Hanbal mosque, Khalid Ahmed Ismael, adding, “His soul was connected to the mosque.”

Ismael recalled how, without being prompted, al-Baghdadi — a nom de guerre he adopted when he became a militant — would lead the other boys in cleaning the house of worship. And he quickly outdid the other boys in the memorization and recitation of scripture.

At age 20, in 1991, al-Baghdadi enrolled in the Shariah college of Baghdad University, according to school records obtained from Iraq’s intelligence agency.

He earned a bachelor’s degree, and then enrolled at Saddam University, an institution dedicated to Islamic studies, where he earned a master’s degree and a doctorate in topics related to Islamic scripture.

To pay for his studies, he taught Quranic classes at al-Haj Zaidan Mosque in the Topchi neighborhood of Baghdad, where his pupils referred to him as “Sheikh Ibrahim.”

In 2003, as military jets sliced the sky over Baghdad and the U.S. invasion to topple Saddam Hussein began, al-Baghdadi told his students that he was heading home.

Less than a year later, he was arrested by U.S. forces near Fallujah. Security officials say al-Baghdadi was swept up in a raid targeting his brother-in-law, who had taken up arms against the U.S. occupation.

Al-Baghdadi spent 11 months in a detention center at Camp Bucca, according to declassified Pentagon records. He was released in late 2004.

Al-Baghdadi’s clout inside the Islamic State group years later became clear when security forces captured a senior leader of the insurgency, said Abu Ali al-Basri, the director general of Iraqi intelligence.

At a checkpoint in Baghdad in March 2010, Iraqi agents arrested Manaf al-Rawi, believed to be one of the executioners of an American contractor, Nick Berg. Under interrogation, al-Rawi named al-Baghdadi as one of the group’s coordinators, using al-Baghdadi’s nom de guerre at the time, Abu Dua.

“I directly sent word to the prime minister with the names of three people we deemed important based on the interrogation of Manaf al-Rawi,” al-Basri said. “One of the three was Baghdadi.”

Not long after, in May 2010, the insurgents announced their new leader: It was Abu Dua, who introduced himself to the world as “Abu Bakr al-Baghdadi.”

In 2014, when he ascended the pulpit of a mosque in Mosul to declare the caliphate, it was the first time a video appeared that showed his face uncovered.

Al-Baghdadi’s reclusiveness fed rumors of his demise, with many news outlets carrying speculative reports of his death, all of which proved to be untrue. Each time, he resurfaced in audio recordings, and later videos.

Some who knew al-Baghdadi the longest wondered if it was his very nature that accounted for his ability to evade capture for so long, and not just his extreme security measures.

Hussam Mehdi, an ISIS member who first met al-Baghdadi at Camp Bucca and is now in jail in Baghdad, said his enduring memory of al-Baghdadi was of him walking back and forth along the fence line — by himself.

“It’s something I have wondered about: a man who was totally alone, a person who doesn’t socialize, just ‘salaam alaikum,’ and then moves on,” Mehdi said. “I wonder if it’s because he likes to be alone that isolation came easily to him.”

Mehdi thought back to the men who had come before al-Baghdadi at the helm of the Islamic State group.

“Abu Musab was killed,” he said. “Abu Omar was killed. But Abu Bakr lasted.”