• Founder of the terrorist group al Qaeda
• Linked to many terrorist attacks around the world, most notably 9/11

Born in 1957 in Saudi Arabia, Osama bin Laden is one of 53 children of the Saudi construction tycoon Muhamad Awad bin Laden, who moved to Saudi Arabia from Yemen and set up a number of successful construction and contracting ventures and amassed a fortune of nearly $5 billion. Of this sum, Osama bin Laden is believed to have inherited as much as $300 million when his father died in the 1960s.

When the former Soviet Union invaded Afghanistan in 1979, bin Laden proclaimed that it was the duty of all Muslims to fight against the Soviets. From that point forward, he became increasingly affiliated with Muslim extremist groups such as Egyptian Islamic Jihad. Starting in the mid-1980s, bin Laden began to establish training camps in Afghanistan, initially for the war against the Soviets, but later to fight against other targets worldwide. He attracted thousands of recruits from Saudi Arabia, Algeria, Egypt, Yemen, Pakistan and Sudan.

Using his family's fortune, bin Laden provided support and training for the mujahedeen, or "freedom fighters," who were seeking to repel the Soviet invaders. He formed a group called Maktab al-Khidimat, which was composed of Muslim volunteers who shared his ideology. For them, this fight against the Soviets became a "jihad," or Islamic Holy War.

At this time, bin Laden received some help from the American CIA (the U.S. was opposed to Soviet expansion), which bought vast quantities of weapons, ammunition, and supplies and sent these to the Pakistani intelligence agency, which in turn distributed them to the mujahedeen. The U.S. did not, however, train or directly finance bin Laden's forces. The Arabs had their own sources of funding and support. What training was provided came from Pakistan.

The Soviets were forced out of Afghanistan in 1989 and the United States subsequently terminated its aid to the Afghanis. By this time, bin Laden had acquired a sizable following, which he began to refer to as "al Qaeda," an Arabic term meaning "the Base." (The foundation for this organization had been laid by bin Laden's mentor, Abdullah Azzam, a longtime influential figure in the Muslim Brotherhood and the historical leader of Hamas.) Bin Laden changed the focus of al Qaeda from fighting the Soviets to fighting all non-Muslims in the region. His new enemies were the American forces that were left behind in Afghanistan and their Middle Eastern allies.

Expecting a hero's welcome after the war against the USSR, bin Laden moved back to Saudi Arabia. Not received by the Saudis as the liberator he believed himself to be, bin Laden soon became an outspoken critic of Saudi authorities, who grew increasingly uncomfortable with his presence and his rhetoric.

Bin Laden's anti-Americanism intensified during the 1991 Gulf War against Iraq, when U.S. troops were stationed in Saudi Arabia. According to a September 14, 2001 New York Times report: "The presence of American soldiers in Saudi Arabia, the birthplace of the Prophet Muhammad and the home of the two holiest Muslim shrines, enraged Mr. bin Laden and other Arab militants." He and his associates also characterized U.S. support for Israel as an affront to Islam.

As bin Laden continued to condemn the Saudi government for permitting its land to be "polluted" by the presence of American "infidels," the royal family stripped him of his travel rights and then his Saudi citizenship in 1991, and eventually expelled him from the country. At that point bin Laden took his organization to Sudan, where a hard-line Islamic militant government had recently come to power. In 1996, however, under pressure from the U.S., Sudan also expelled bin Laden. This time he relocated to Afghanistan, where he was welcomed as an honored "guest" by the Taliban, a brutal, authoritarian Islamic group that had assumed political leadership of that country.

Bin Laden is known to have financed, inspired, or directly organized many terrorist attacks. He has been directly linked to the August 7, 1998 bombings of the U.S. embassies in Kenya and Tanzania -- attacks that killed a combined 224 people. He was also a mastermind of the October 2000 bombing of the USS Cole in Yemen, which killed 17 American sailors. Moreover, he has been implicated in the killings of Western tourists by militant Islamic groups in Egypt; bombings in France by Islamic extremist Algerians; the 1992 bombing of a hotel in Yemen; the 1995 detonation of a car bomb in Riyadh, Saudi Arabia; a 1995 truck bomb in Dhahran, Saudi Arabia that killed 19 U.S. servicemen; and the 1995 assassination attempt on Egyptian President Hosni Mubarak. He maintained a safe-house in Pakistan for Ramzi Ahmed Yousef, the convicted mastermind of the 1993 World Trade Center bombing, and he sheltered Omar Abdel Rahman, who was also convicted for his role in that bombing. Most famously, bin Laden authorized the September 11, 2001 al Qaeda airplane hijackings leading to the attacks on the World Trade Center and Pentagon, killing more than 3,000 people.

The United States responded to 9/11 militarily, quickly overthrowing the Taliban regime which had given bin Laden safe haven in Afghanistan. Bin Laden went into hiding and his whereabouts are presently unknown, though he is thought to be somewhere in the mountains between Afghanistan and Pakistan. He occasionally releases audio or video tapes (aired by the Al Jazeera broadcast network) praising attacks against American interests.

"I have sworn to only live free," said bin Laden in one audiotape. "Even if I find bitter the taste of death, I don't want to die humiliated or deceived. . . . The jihad is continuing with strength, for Allah be all the credit, despite all the barbarity, the repressive steps taken by the American Army and its agents, to the extent that there is no longer any mentionable difference between this criminality and the criminality of Saddam."

Expressing his contempt for the United States, bin Laden has said: "Hostility toward America is a religious duty, and we hope to be rewarded for it by God."

Bin Laden's closest living associate is Dr. Ayman al-Zawahiri, his personal physician and chief Lieutenant.