In his death on May 2, 2011, Osama bin Laden kept a promise made in a 2006 audio message.
Alluding to the United States' hunt for him, the al-Qaeda leader stated his determination to avoid capture: "I swear not to die but a free man."
His death ends the largest manhunt in history that began a decade ago involving thousands of US troops in Afghanistan and tens of thousands of Pakistani soldiers in the rugged mountains along the border.
Whether reviled as a terrorist and mass murderer or hailed as the champion of oppressed Muslims fighting injustice and humiliation, bin Laden changed the course of history.
Challenging the might of the US, the most powerful nation ever, he masterminded a string of attacks against it and then built a global network of allies to wage a war intended to outlive him.
The man allegedly behind the suicide hijack attacks of September 11, 2001, was the nemesis of former US President George Bush, who pledged to take him "dead or alive" and whose two terms were dominated by a "war on terror" against his al-Qaeda network founded in 1988.
With his long grey beard and wistful expression, bin Laden became one of the most instantly recognisable people on the planet. His gaunt face stared out from propaganda videos and framed a US website offering a $25 million bounty. In 2007, that bounty was doubled.
Born in Saudi Arabia in 1957, one of more than 50 children of millionaire businessman Mohamed bin Laden, he lost his father while still a boy.
Osama's first marriage, to a Syrian cousin, came at the age of 17, and he is reported to have at least 23 children from at least five wives. Part of a family that made its fortune in the oil-funded Saudi construction boom, bin Laden was a shy boy and an average student, who took a degree in civil engineering.
A book by US writer Steve Coll, The Bin Ladens, suggested the death in 1988 of his extrovert half-brother Salem was an important factor in Osama's radicalisation.
The elite Al Thagher Model School in the Saudi city of Jeddah also exposed him to the ideas of political Islam.
Steve Coll wrote that “bin Laden's introduction to Islam as the basis for political, and potentially violent-activism, was through informal sessions run by the Al Thagher's teachers”.
A key influence on Osama was Dr Abdullah Azzam, a Palestinian professor and member of the Palestinian Muslim Brotherhood.
During his stay at Abdulaziz University, Saudi Arabia, Osama was hugely influenced by Azzam's radical views.
It is believed that Azzam encouraged bin Laden to solicit funds and recruit Arab fighters for the Afghan war against Russians.
The US' Central Intelligence Agency provided a conduit for him to join the fight in Afghanistan.
Osama’s slide away from the US was first observed when he raised objection to US military presence in Saudi Arabia during the first Gulf war against Iraq.
The Saudi monarch smelled rebellion in Laden and expelled him 1991. He was stripped of his Saudi citizenship in 1994 and his assets were frozen.
Trail of attacks
He declared war against the very United States which had spent billions of dollars bankrolling the Afghan resistance in which he had fought.
Al-Qaeda embarked on a trail of attacks, beginning with the 1993 World Trade Center bombing that killed six and first raised the spectre of Islamist extremism spreading to the United States.
Bin Laden was the prime suspect in bombings of US servicemen in Saudi Arabia in 1995 and 1996 as well as attacks on U.S. embassies in Kenya and Tanzania in 1998 that killed 224.
In October 2000, suicide bombers rammed into the USS Cole warship in Yemen, killing 17 sailors, and al-Qaeda was blamed.
Disowned by his family and stripped of Saudi citizenship, bin Laden had moved first to Sudan in 1992 and later resurfaced in Afghanistan before the Taliban seized Kabul in 1996.
With his wealth, largesse and shared radical Muslim ideology, bin Laden soon eased his way into inner Taliban circles as they imposed their rigid interpretation of Islam.
From Afghanistan, bin Laden issued religious decrees against US soldiers and ran training camps where fighters were groomed for a global campaign of violence.
Recruits were drawn from Central, South and Southeast Asia, the Middle East, Africa and even Europe by their common hatred of the United States, Israel and moderate Muslim governments, as well as a desire for a more fundamentalist brand of Islam.
After the 1998 attacks on two of its African embassies, the United States fired dozens of cruise missiles at Afghanistan, targeting al Qaeda training camps. Bin Laden escaped unscathed.
The Taliban paid a heavy price for sheltering bin Laden and his fighters, suffering a humiliating defeat after a US-led invasion in the weeks after the September 11, 2001 attacks.
Escape to Pakistan
Al-Qaeda was badly weakened, with many fighters killed or captured. Bin Laden vanished -- some reports say US bombs narrowly missed him in late 2001 as he and his forces slipped out of Afghanistan's Tora Bora mountains and into Pakistan.
But the start of the Iraq war in 2003 produced a fresh surge of recruits for al-Qaeda due to opposition to the US invasion.
Apparently protected by the Afghan Taliban in their northwest Pakistani strongholds, bin Laden also built ties to an array of south Asian militant groups and backed a bloody revolt by the Pakistani Taliban against the Islamabad government.
Amid a reinvigorated al-Qaeda propaganda push, operatives or sympathisers were blamed for attacks from Indonesia and Pakistan to Iraq, Turkey, Egypt, Kenya, Morocco, Algeria, Mauritania, Tunisia, Saudi Arabia, Yemen, Spain, Britain and Somalia.
Tougher security in the West and killings of middle-rank al-Qaeda men helped weaken the group, and some followers noted critically that the last successful al Qaeda-linked strike in a Western country was the 2005 London bombings that killed 52.
But, by his own account, not even bin Laden anticipated the full impact of using 19 suicide hijackers to turn passenger aircraft into guided missiles and slam them into buildings that symbolised US financial and military power.
Nearly 3,000 people died when two planes struck New York's World Trade Center; a third hit the Pentagon in Washington, and a fourth crashed in a field in rural Pennsylvania after passengers rushed the hijackers.
"Here is America struck by God Almighty in one of its vital organs," bin Laden said in a statement a month after the September 11 attacks, urging Muslims to rise up and join a global battle between "the camp of the faithful and the camp of the infidels".
In video and audio messages over the next seven years, the al-Qaeda leader goaded Washington and its allies. His diatribes lurched across a range of topics, from the war in Iraq to US politics, the subprime mortgage crisis and even climate change.
A gap of nearly three years in his output of video messages revived speculation he might be gravely ill with a kidney problem or even have died, but bin Laden was back on screen in September 2007, telling Americans their country was vulnerable despite its economic and military power.