HTS traces its origins to al-Qaeda, but in recent years has actively sought to rebrand itself as a nationalist force far removed from its jihadist past and intent on removing Assad.
As the militants marched into Damascus earlier this month, its leaders spoke of creating a Syria for all Syrians. However, the US, UK, UN and other countries, including Turkey, which supports some Syrian rebels, still label it a terrorist organization.
The group took control of most of the region, home to 4.5 million people, in 2017, restoring stability after years of civil war.
The administration, known as the Salvation Government, provides water and electricity distribution, garbage collection and road surfacing.
Taxes collected from businesses, farmers and crossings with Turkey fund its government services as well as military operations.
“Under Assad, they said Idlib was a forgotten city,” said Dr. Hamza Almaraweh, a cardiologist, as he treated patients at a hospital housed in an old post office.
He moved from Aleppo with his wife in 2015 as the war there intensified, but had no plans to return, even though the city is under rebel control.
“We’ve seen a lot of development here. There are many things in Idlib that did not exist under the Assad regime.”