(CNN) -- Here's a look at Operation Enduring Freedom which began on October 7, 2001, with allied air strikes on Taliban and al Qaeda targets. The United States linked the September 11, 2001, terrorist attacks to al Qaeda, a group which operated under the Taliban regime's protection in Afghanistan. The operation was launched to stop the Taliban from providing a safe haven to al Qaeda and to stop al Qaeda's use of Afghanistan as a base of operations for terrorist activities.
Timeline: October 7, 2001 - Operation Enduring Freedom begins. President George W. Bush announces that U.S. and British forces have begun airstrikes on Taliban and al Qaeda targets in Afghanistan. Airstrikes continue for five days.
October 14, 2001 - The Taliban offers to discuss giving Osama bin Laden to a third country for trial if the United States provides evidence of bin Laden's involvement in the 9-11 attacks. The White House rejects the offer.
October 19, 2001 - The Pentagon reports that U.S. forces have searched a compound used by Taliban leader Mullah Mohammed Omar. This is the first acknowledged ground action of OEF.
October 26, 2001 - British Armed Forces Minister Adam Ingram tells the House of Commons that Britain is deploying a force of 4,200 personnel military to Afghanistan.
November 1, 2001 - Turkey announces it will deploy troops to Afghanistan. Australia and Canada also agree to send forces.
November 5, 2001 - U.S. Defense Secretary Donald Rumsfeld announces that the United States has more than doubled the number of its troops based in Afghanistan.
November 6, 2001 - German Chancellor Gerhard Schroeder offers up to 3,900 troops for the effort.
November 7, 2001 - Italy says it will provide 2,700 troops.
November 9, 2001 - The Netherlands announces that they are prepared to send up to 1,400 troops to Afghanistan.
November 13, 2001 - U.S. airstrikes and ground attacks by the anti-Taliban Afghan Northern Alliance lead to the fall of Kabul.
November 16, 2001 - French troops deploy for Afghanistan.
November 20, 2001 - The bodies of four journalists missing in Afghanistan are recovered. The journalists are on the road between Jalalabad and Kabul when their convoy is attacked.
November 22, 2001 - Poland agrees to contribute up to 300 soldiers to OEF.
December 2-5, 2001 - The United Nations hosts the Bonn Conference in Germany. The resulting Bonn Agreement creates an Afghan Interim Authority and outlines a process for creating a new constitution and choosing a new government.
December 7, 2001 - The Taliban loses its last major stronghold as the city of Kandahar falls and opposition forces enter.
December 20, 2001 - The United Nations authorizes the International Security Assistance Force (ISAF) to provide security support to the Afghans. The United Kingdom agrees to lead the force initially.
December 22, 2001 - Hamid Karzai is sworn in as head of an interim power-sharing government.
January 23, 2002 - Wall Street Journal reporter Daniel Pearl is abducted in Karachi, Pakistan, by the National Movement for the Restoration of Pakistani Sovereignty, who claim the kidnapping is in retaliation for the detention of Pakistanis at Guantanamo.
January 27, 2002 - Media organizations receive the first email from Pearl's captors, which includes photos of reporter Daniel Pearl handcuffed with a gun to his head.
February 21, 2002 - FBI and Pakistani officials announce they have received a videotape that confirms Pearl has been killed.
March 25, 2002 - Defense Secretary Donald H. Rumsfeld announces that there are plans under way for U.S. and coalition forces to help train and create an Afghan national army.
June 13, 2002 - Hamid Karzai is elected to a two-year presidential term by the grand council, a gathering of Afghanistan's tribal leaders.
August 9, 2003 - NATO assumes responsibility for the ISAF mission.
January 2004 - Afghanistan passes a new constitution by consensus.
October 9, 2004 - Afghanistan's first direct democratic election is held.
December 7, 2004 - Hamid Karzai is sworn in as the first democratically elected president of Afghanistan.
September 18, 2005 - The first parliamentary and provincial elections are held in more than three decades.
March 1, 2006 - President George W. Bush makes his first visit to Afghanistan, and meets with President Hamid Karzai.
February 27, 2007 - A suicide bomber blows up a checkpoint at Bagram Air Base, killing more than 20. Taliban insurgents claim Vice President Dick Cheney was the target of the attack.
February 15, 2007 - President Bush calls on NATO to increase troops in Afghanistan. There are already about 50,000 U.S. and NATO troops there.
May 11, 2007 - The Taliban's top military commander, Mullah Dadullah, is killed in a U.S.-led coalition operation.
July 19, 2008 - Democratic presidential nominee Barack Obama makes his first visit to Afghanistan.
December 15, 2008 - President Bush makes a surprise visit to Afghanistan. It is his second and last visit as president.
February 17, 2009 - President Obama approves a troop increase of 17,000 for Afghanistan. There are currently about 38,000 U.S. troops serving in Afghanistan.
June 30, 2009 - U.S. soldier Sgt. Bowe R. Bergdahl is taken hostage by the Taliban.
August 20, 2009 - Afghanistan holds its second election. Voting fraud allegations lead to the scheduling of a presidential runoff vote on November 7.
October 31, 2009 - A runoff election is canceled when Foreign Minister Abdullah Abdullah drops out, leaving Karzai as the only candidate and winner by default.
November 19, 2009 - Hamid Karzai is sworn in for a second term as president.
December 1, 2009 - President Obama announces the deployment in 2010 of 30,000 additional U.S. troops. This new deployment will bring the U.S. total to almost 100,000 troops, in addition to 40,000 NATO troops.
January 2010 - Representatives from over 60 nations meet in London for the International Conference on Afghanistan, pledging support the development of the Afghan National Security Forces.
March 28, 2010 - President Obama makes his first visit to Afghanistan as president.
August 1, 2010 - The Netherlands becomes the first NATO member to pull combat troops out of Afghanistan.
August 5, 2010 - Ten aid workers are killed by gunmen in Badakhshan, Afghanistan. Among the dead are six Americans, two Afghans, a Briton and a German.
September 18, 2010 - Parliamentary elections are held. Results are delayed following allegations of fraud.
December 3, 2010 - President Obama visits for the third time, the second as president.
May 2, 2011 - In the early morning hours, a small group of U.S. Forces, including Navy Seals, raid a compound in Abbottabad, Pakistan. In the ensuing firefight, al Qaeda leader Osama bin Laden is killed. DNA samples are taken to confirm his identity, then his body is buried at sea.
June 22, 2011 - President Obama announces that all of the 33,000 additional U.S. forces deployed to Afghanistan in December 2009 will return home within the next 15 months. He also announces that U.S. combat operations in Afghanistan will end by 2014.
July 13, 2011 - The first batch of departing U.S. soldiers leaves Afghanistan. About 650 U.S. soldiers leave the northeastern province of Parwan.
August 6, 2011 - Insurgents shoot down a helicopter in central Afghanistan, killing 30 U.S. coalition members, seven Afghan troops and a civilian interpreter.
August 10, 2011 - NATO announces that Coalition forces in Afghanistan have killed Mullah Mohibullah, the Taliban leader and insurgent responsible for the downing of the helicopter that left 38 U.S. and Afghan personnel dead.
August 2011 - August becomes the deadliest month for U.S. forces in Afghanistan since the conflict began, with 71 U.S. casualties.
September 10, 2011 - Two Afghan civilians are killed and 77 U.S. troops and 25 Afghan workers are wounded when a Taliban suicide bomber detonates a large vehicle-borne improvised explosive device at the entrance of Combat Outpost Sayed Abad, an ISAF base in Afghanistan's Wardak province.
September 13, 2011 - Taliban militants open fire near the U.S. Embassy and NATO's International Security Assistance Force headquarters after they storm into a nearby abandoned building. Three police officers and one civilian are killed and security forces kill six militants. Taliban spokesman Zabiullah Mujahid tells CNN their target is the U.S. Embassy, governmental organizations and other foreign organizations.
February 1, 2012 - Defense Secretary Leon Panetta announces that the U.S. hopes to end their combat mission in Afghanistan in 2013, transitioning primarily to a training role.
February 21, 2012 - Violent protest break out in Afghanistan over reports that Qurans were burned at a U.S. military base. A military official says the Qurans were removed from a detainee center library at Bagram Airfield because they had "extremist inscriptions" on them. As of March 2, the unrest has left at least 41 people dead, including 6 U.S. soldiers, and hundreds more wounded.
March 11, 2012 - An American soldier based at Camp Belambay, Afghanistan allegedly goes on a house-to-house shooting spree in two villages in Kandahar province, killing 17 people. (Initial reports indicated 16 people had died.)
April 8, 2012 - The U.S. and Afghanistan sign a landmark deal that gives Afghan authorities an effective veto over special operations night raids. The deal prevents NATO's ISAF from conducting raids without the permission of Afghan officials.
April 18, 2012 - The Los Angeles Times releases pictures believed to have been taken in 2010 of U.S. 82nd Airborne Division paratroopers posing with the body parts of dead insurgents in Afghanistan.
May 2, 2012 - President Obama marks the first anniversary of the death of Osama bin Laden with an unannounced trip to Afghanistan. According to the White House, his speech is the first TV address to the nation from a war zone on foreign soil. Obama and Afghan President Hamid Karzai also sign a strategic partnership agreement for 10 years of U.S. support of Afghanistan after the 2014 troop withdrawal.
June 9, 2012 - French President Francois Hollande announces his plan to withdraw combat forces by year's end will start next month.
September 1, 2012 - Two suicide bombers strike a joint U.S.-Afghan military base, killing 13 people and injuring 78 others. One bomber attacks the base on foot and another one detonates a truck. No international coalition service members are killed in the attack, but two are wounded. The Taliban claim responsibility for the attack.
September 2, 2012 - U.S. Special Operations Forces temporarily suspends training of some 1,000 Afghan local police recruits while they double-check the background of the current police force, following a rise in insider attacks against NATO troops by Afghan forces.
September 14, 2012 - Fifteen insurgents wearing U.S. Army uniforms attack Camp Bastion, a U.S. and British military complex. Fourteen insurgents and two U.S. Marines are killed and six AV-8B Harrier jets are destroyed during the attack. Nine others are wounded, one civilian and eight coalition personnel. Britain's Prince Harry, an Apache helicopter pilot, is deployed to Camp Bastion; he is unhurt during the incident.
September 20, 2012 - It is announced that the surge of U.S. forces in Afghanistan has ended and the last several hundred surge troops have left the country.
December 2012 - France pulls its last troops engaged directly in combat out of Afghanistan. The remaining French troops, about 1,500, will remain in Afghanistan for approximately six months to remove equipment and to help train Afghan forces.
June 18, 2013 - Afghan National Security Forces formally take over combat operations.
May 27, 2014 - President Obama announces that the United States combat mission in Afghanistan will end in December 2014.
May 31, 2014 - President Barack Obama announces the release of Bowe Bergdahl, the U.S. soldier held captive by the Taliban for five years.