ISIS leader Abu Bakr Al Baghdadi was buried at sea and given his religious rites according to Islamic custom after he killed himself in a commando raid in northern Syria, US officials have said.
His remains were delivered to sea from an aircraft but the location was not disclosed.
Al Baghdadi died after detonating a suicide vest when he fled into a tunnel as elite US special forces closed in, the US government said.
Gen Mark Milley, Chairman of the Joint Chiefs of Staff, said on Monday that the US military disposed of Al Baghdadi's remains "appropriately, in accordance with our [standard operating procedures] and in accordance with the law of armed conflict".
The UAE, a member of the coalition to fight ISIS, said the terrorist leader's death "signifies a victory for all nations united in the fight against terrorism and extremism".
After Navy Seals killed Al Qaeda founder Osama bin Laden in a 2011 raid into Pakistan, he was taken to the aircraft carrier USS Carl Vinson.
There, his body was washed before being covered in a white sheet, and religious remarks translated into Arabic were read out.
But bin Laden was killed by a gunshot wound to the head, while Al Baghdadi blew himself up, so his death rituals would not have been so straightforward.
Bin Laden's burial at sea sparked mixed reactions, with a prominent imam saying the US broke Islamic custom by not burying him on land.
The US did not want his resting place to becoming a shrine for extremist followers.
In America, some questioned why the man responsible for the September 11 attacks that killed nearly 3,000 people was laid to rest with such respect.
Gen Milley did not give details about Al Baghdadi's last rites. He said that before the disposal of his remains, they had been taken to a secure facility to confirm his identity with DNA tests.
"It's been done and is complete," Gen Milley said.
Syrian Kurds claimed to be a key source of the intelligence that led the US to Al Baghdadi after years of tracking him.
And an unidentified US military dog became an unlikely hero of the raid, incurring wounds as it chased Al Baghdadi down a dead-end tunnel underneath his north-western Syria hideout, where the extremist blew himself and three children up.
The US military basked in success Monday after eliminating the founder and spiritual guide of ISIS, capping a years-long campaign to crush the extremist organisation that had at one point created a "caliphate" the size of England.
"His death marks a devastating blow to the remnants of ISIS," Defence Secretary Mark Esper said.
He praised the nearly 100 troops flown by helicopter to the rural compound in Idlib in a mission that required co-ordination with Russians, Kurds, Turks and President Bashar Al Assad's regime to stop the aircraft being fired on.
"They executed the raid in all of its facets brilliantly," Mr Esper said.
Mr Miley said no one was injured in the operation, despite the US team taking fire when they arrived. They took two men prisoner.