During the 1979-1989 Soviet-Afghan War in Afghanistan, in which the Soviet Union gave support to the communist Afghan government, Muslim insurgents, known as the mujahideen, rallied to fight a jihad (or holy war) against the invaders. Among them was a Saudi Arabian—the 17th child (of 52) of a millionaire construction magnate—named Osama bin Laden, who provided the mujahideen with money, weapons and fighters.

Along with Abdullah Azzam, a Palestinian Sunni Islamic scholar, preacher and mentor of bin Laden, the men began to grow a large financial network, and when the Soviets withdrew from Afghanistan in 1989, al Qaeda was created to take on future holy wars. For Bin Laden, that was a fight he wanted to take globally.

Azzam, conversely, wanted to focus efforts on turning Afghanistan into an Islamist government. When he was assassinated in a car bombing in Pakistan in 1989, bin Laden was left as the group’s leader.

Exiled by the Saudi regime, and later stripped of his citizenship in 1994, bin Laden left Afghanistan and set up operations in Sudan, with the United States in his sights as enemy No. 1. Al Qaeda took credit for the attack on two Black Hawk helicopters during the Battle of Mogadishu in Somalia in 1993, as well as the World Trade Center Bombing in New York in 1993, and a car bombing in 1995 that destroyed a U.S.-leased military building in Saudi Arabia. In 1998 the group claimed responsibility for attacks on U.S. embassies in Kenya and Tanzania and, in 2000, for the suicide bombings against the U.S.S. Cole in Yemen, in which 17 American sailors were killed, and 39 injured.

Expelled from Sudan in 1996, bin Laden returned to Afghanistan under protection of the Taliban, where he provided military training to thousands of Muslim insurgents. In 1996, he announced a fatwa against the United States, “Declaration of War Against the Americans Occupying the Land of the Two Holy Places,” with a second declaration of fatwa issued in 1998, citing protests against the United States, Israel and other allies.

“The U.S. today, as a result of the arrogant atmosphere, has set a double standard, calling whoever goes against its injustice a terrorist,” bin Laden said in a 1997 interview with CNN. “It wants to occupy our countries, steal our resources, impose on us agents to rule us, and then wants us to agree to all this.”

WATCH: How Decades of Instability Gave Rise to al Qaeda

According to the Council on Foreign Relations, the terrorist network’s violent opposition of the United States stemmed from its support of “infidel” governments, including those of Israel, Saudi Arabia and Egypt, along with the United Nations, and America’s involvement in the 1991 Persian Gulf War and in Somalia’s ’92-’93 Operation Restore Hope mission.

“In particular, al Qaeda opposed the continued presence of American military forces in Saudi Arabia (and elsewhere on the Saudi Arabian peninsula) following the Gulf War,” the Council reports, adding that “al Qaeda opposed the United States Government because of the arrest, conviction and imprisonment of persons belonging to al Qaeda or its affiliated terrorist groups or those with whom it worked. For these and other reasons, Bin Laden declared a jihad, or holy war, against the United States, which he has carried out through al Qaeda and its affiliated organizations.”

After September 11, 2001, when four passenger airplanes were hijacked by al Qaeda terrorists, resulting in the mass murder of 2,977 victims in New York, Washington, D.C. and Somerset County, Pennsylvania, Bin Laden was named as the orchestrator and prime suspect.

The attacks led to the U.S. War in Afghanistan, a.k.a. Operation Enduring Freedom, launched on October 7, 2001, driving bin Laden’s protector, the Taliban, from power, although the war continued. Bin Laden was forced into hiding—he had an FBI-issued $25 million bounty on his head. Bin Laden evaded authorities until May 2, 2011, when a covert operation by U.S. Navy SEALs, shot and killed the terrorist leader at a private compound in Abbottabad, Pakistan.

The U.S. withdrew from Afghanistan in August 2021, and the Taliban resumed power there.

Read more: How SEAL Team 6 Took Out Osama bin Laden

While al Qaeda was weakened, the group began “quietly rebuilding” following instability in the wake of the Arab Spring, according to the Council on Foreign Relations. “… It appears that al Qaeda was among the regional forces that benefited most from the (2011) Arab Spring’s tumult,” the nonpartisan think tank reported.

Ayman al-Zawahiri, who went into hiding after the September 11 attacks, became leader of al Qaeda after bin Laden's killing. On July 31, 2022, he was killed in a U.S. drone strike in Kabul, Afghanistan, ending a two decade-long manhunt.

Other jihadist groups, including the Islamic State—often called ISIS or ISIL—remain active in their fight against the United States and Western culture.

The 9/11 Commission Report, July 22, 2004, The 9/11 Commission
“’Black Hawk Down’ Anniversary: al Qaeda’s Hidden Hand,” October 4, 2013, ABC News
"Islamic State, the Taliban and Al Qaeda: How Are They Different?” August 22, 2017, Forces Network
“Osama bin Laden Fast Facts,” (updated) June 6, 2017, CNN
“Al-Qaeda’s Resurrection,” March 6, 2018, Council on Foreign Relations
“Frontline: Background: Al Qaeda,” January 7, 2002, PBS
“Quick Guide: Al Qaeda,” BBC
“Al Qaeda,” (updated) June 6, 2012, Council on Foreign Relations