The fall of President Bashar al-Assad has raised critical questions about the future of Syria and who speaks for its people.
One group aiming for that role is Hayat Tahrir al-Sham (HTS), which, under the leadership of Abu Mohammad al-Golani, spearheaded the opposition advance that toppled Assad.
But who is al-Golani? And what does the group he leads stand for?
What do we know about Hayat Tahrir al-Sham?
Hayat Tahrir al-Sham, formerly known as the Nusra Front, was Al Qaeda's official wing in the Syrian war until breaking ties in 2016.
Emerging as the Syrian branch of the Islamic State group's predecessor in 2012 and then known as Jahbat al-Nusra, the group would eventually disavow ISIS and pledge allegiance to Al Qaeda.
Jahbat al-Nusra then broke with Al Qaeda to focus on the local Syrian conflict rather than global jihad.
HTS, led by Abu Mohammed al-Golani, has long been the dominant force in the Idlib region, part of an arc of the north-west where rebels maintained a foothold despite Assad's gains elsewhere.
It has been designated a terrorist group by Australia, the United States, Russia and Türkiye.
A senior White House official described HTS as an "umbrella organisation" and that there was a "broad kind of kaleidoscope of groups" operating in the region.
Hussein Ibish, a senior resident scholar at the Arab Gulf States Institute, told RN Breakfast it was "very interesting" that HTS had allowed Syria's prime minister, Mohammed Ghazi al-Jalali, to remain as a caretaker.
"That's a very interesting move because rather than arresting him, they are letting him continue in a position of authority, and that I think is at least designed to send a message that they're more interested in governance than they are in score-settling," he said.
However, Mr Ibish says HTS has a "very grim history", adding, "they don't have a great track record of governance".
"The only thing you could say is, 'well, this wasn't real governance, they were just using [Idlib] as a base, a broader revolutionary project that has now succeeded and now they'll try to govern in a genuinely inclusive way' — well, we'll see," he said.
"Scepticism is warranted."
Who is Abu Mohammed al-Golani?
Abu Mohammed al-Golani has spent years working to remake his public image, renouncing longtime ties to Al Qaeda and depicting himself as a champion of pluralism and tolerance.
As he entered Damascus behind his victorious fighters on Sunday, he even dropped his nom de guerre and referred to himself by his real name, Ahmad al-Sharaa.
Hours after Damascus's capture, the 42-year-old al-Sharaa made his first appearance in the city's landmark Umayyad Mosque, declaring Assad's fall "a victory for the Islamic nation."
Al-Sharaa, who has been labelled a terrorist by the United States, and his insurgent force HTS — many of whose fighters are jihadis — now stand to be a major player.
For years, al-Sharaa worked to consolidate power while bottled up in the province of Idlib in Syria's north-west corner as Assad's Iranian- and Russian-backed rule over much of the country appeared solid.
He manoeuvred among extremist organisations while eliminating competitors and former allies.
He sought to polish the image of his de facto "salvation government" that has been running Idlib to win over international governments and reassure Syria's religious and ethnic minorities. And he built ties with various tribes and other groups.
Along the way, he shed his garb as a hard-line Islamist guerilla and put on suits for press interviews, talking of building state institutions and decentralising power to reflect Syria's diversity.
"Syria deserves a governing system that is institutional, not one where a single ruler makes arbitrary decisions," he said in an interview with CNN last week, offering the possibility HTS would eventually be dissolved after Assad falls.
"Don't judge by words, but by actions," he said.
Al-Golani's beginnings in Iraq
Al-Golani's ties to Al Qaeda stretch back to 2003, when he joined insurgents battling US troops in Iraq.
The Syrian native was detained by the US military but remained in Iraq.
During that time, Al Qaeda usurped like-minded groups and formed the extremist Islamic State of Iraq, led by Abu Bakr al-Baghdadi.
In 2011, a popular uprising in Syria against Assad triggered a brutal government crackdown and led to an all-out civil war.
Al-Golani's prominence grew when al-Baghdadi sent him to Syria to establish a branch of Al Qaeda called the Nusra Front — later renamed Hayat Tahrir al-Sham.
The United States still designates HTS a terrorist organisation and the US government has put a $10 million bounty on al-Golani.
"Rewards for Justice is offering a reward of up to $10 million for information on Muhammad al-Jawlani, also known as Abu Muhammad al-Golani and Muhammad al-Julani," the website reads.
What has the US said about al-Golani and HTS?
When asked if the United States would lift its terrorist designation, a senior White House official said America was "focused on supporting Syrians as they determine their own future".
"Whether or not and how [a designation lift] would be addressed I think is something that we'll have to look to down the line," the official said.
"But again, I think what we'll be looking for in particular is some of the statements that have been made actually putting into action. I think that would be quite important."
The White House has called the collapse of the Assad regime a "momentous event" and a "fundamental act of justice".
"The future here will be written by Syrians," the official said.
"We are not coming up with a blueprint from Washington for the future of Syria. This is written by Syrians. The fall of Assad was delivered by Syrians.
"But I think it's very clear that the United States can provide a helping hand, and we are very much prepared to do so."
AP/Reuters/ABC
