As most Syrian opposition groups raced to Damascus in the wake of the fall of Bashar Al-Assad, Turkish proxies the Syrian National Army (SNA) advanced towards Manbij, which had been controlled by the Kurdish Syrian Democratic Forces (SDF). After heavy fighting around the city, the US and Turkiye struck a deal for the SDF to retreat on 9 December, allowing the SNA to enter the northern town.
The SDF defeated Daesh here in 2016, after which Kurdish groups established an autonomous region in the northeast of Syria with the help of the US. Ankara has said it wants to remove Kurdish control of this area and so the advance of the SNA across northeastern Syria is likely to continue.