Taliban insurgents entered Kabul on Sunday after previously taking control of all of Afghanistan's other major cities apart from the capital.
Prior talks between the Taliban and the Afghan government on a political understanding that could lead to a peace deal, backed by the United States and its allies, have failed to make significant progress.
Here are some of the key dates in the Islamist militant movement's advance in recent months. Other deadly attacks have also occurred, some blamed on the Taliban and some on other jihadist groups including an offshoot of the Islamic State.
U.S. President Joe Biden announces U.S. troops will withdraw from Afghanistan starting on May 1 and ending on Sept. 11, bringing the country's longest war to a close. It was an extension of the previous withdrawal deadline of May 1 agreed to between the United States and the Taliban.
Taliban fighters launch a major offensive on Afghan forces in southern Helmand province. They also attack in at least six other provinces.
The Taliban captures Nerkh district just outside the capital Kabul as violence intensifies across the country.
Senior government officials say more than 150 Afghan soldiers were killed in 24 hours as fighting worsens. They add that fighting is raging in 26 of the country's 34 provinces.
Taliban fighters launch a series of attacks in the north of the country, far from their traditional strongholds in the south. The United Nations envoy for Afghanistan says they have taken more than 50 of 370 districts.
U.S. troops quietly pull out of their main military base in Afghanistan — Bagram air base, an hour's drive from Kabul. It effectively ends U.S. involvement in the war.
The Taliban says it could present a written peace proposal to the Afghan government as soon as August.
Taliban insurgents control about a half of the country's districts, according to the senior U.S. general, underlining the scale and speed of their advance.
The United States vows to continue to support Afghan troops "in the coming weeks" with intensified airstrikes to help them counter Taliban attacks.
The UN says nearly 2,400 Afghan civilians were killed or wounded in May and June in escalating violence, the highest number for those months since records started in 2009.
Zaranj in the south of the country becomes the first provincial capital to fall to the Taliban in years. Many more follow in the ensuing days, including the prized city of Kunduz in the north.
Four more provincial capitals fall in a day, including Kandahar, the country's second-largest city and spiritual home of the Taliban. In the west, another key city, Herat, is overrun. Veteran commander Mohammad Ismail Khan, one of the leading fighters against the Taliban, is captured.
The Canadian government also announces that it intends to take in as many as 20,000 additional refugees from Afghanistan. Immigration Minister Marco Mendicino described the policy change as an expansion of the resettlement program announced late last month.
Taliban fighters take the major northern city of Mazar-e-Sharif and, with little resistance, Pul-e-Alam, capital of Logar province just 70 kilometres south of Kabul. The United States sends more troops to help evacuate its civilians from Kabul as Afghan President Ashraf Ghani says he is consulting with local and international partners on next steps.
Taliban insurgents take the key eastern city of Jalalabad without a fight, effectively surrounding Kabul.
They later take the capital city of Kabul and Afghanistan's government collapses, with the president joining the exodus of citizens and foreigners. Heavily armed Taliban fighters fan out across the capital, and a group of fighters enter the presidential palace.
The Taliban begins to enforce its rule over the wider capital. At least seven people die as thousands of Afghans rush the tarmac at the Kabul airport, hoping to escape the country on evacuation flights.
A spokesperson says the Taliban will respect women's rights within the norms of Islamic law, forgive those who resisted and ensure a secure Afghanistan. The comments are met with skepticism by many Afghans and world leaders.
There is violence in parts of Afghanistan as citizens try to fly the Afghan national flag, and U.S. and Canadian officials continue to try to evacuate foreign nationals from the country. Afghan President Ashraf Ghani defends his decision to flee in a Facebook post, describing it as the only way to prevent bloodshed.
With files from Murray Brewster and The Associated Press