Who are Syria’s key rebel groups shaping post-Assad future?

Syria’s civil war has reached a pivotal moment with the fall of President Bashar Assad, bringing an end to his decades-long rule marked by corruption, repression and foreign intervention. A coalition of opposition forces has broken a prolonged stalemate, dramatically altering the course of the conflict.
However, the Syrian opposition remains a fragmented patchwork of groups with conflicting ideologies and clashing long-term ambitions. Each group is dependent on the support of competing foreign powers, often putting them at odds with one another.
Here’s a closer look at the players shaping the post-Assad landscape in Syria.
The recent lightning offensive that led to the fall of Damascus was spearheaded by Hayat Tahrir al-Sham (HTS), an Islamist militant group led by Abu Mohammed al-Golani, whose real name is Ahmad al-Sharaa.
HTS has a complex history rooted in the Syrian conflict. Initially established as Jabhat al-Nusra in 2011, the group was an al-Qaeda affiliate founded with involvement from Abu Bakr al-Baghdadi, the key jihadi leader who later headed Islamic State (IS).
Known for its jihadi ideology, Jabhat al-Nusra often clashed with other opposition groups, including the main rebel coalition under the Free Syria banner. In 2016, al-Golani severed ties with al-Qaeda and rebranded the group as HTS, later merging it with several smaller Islamist factions.
While HTS’ ideology remains largely aligned with al-Qaeda, the group has shifted its focus to establishing fundamentalist Islamic rule within Syria, distancing itself from IS’ broader ambitions of a global caliphate.
HTS has since cemented its power base in the northwestern province of Idlib, where it acts as the de facto administration. However, allegations of human rights abuses have undermined its efforts to gain broader legitimacy.
HTS is designated a terrorist organization by the UN, the US, Turkey and others. However, the group’s recent offensive appears to align with Ankara’s long-standing goal of ousting Assad, and likely could not have taken place without Turkey’s coordination and support, despite Turkish officials denying direct involvement.
In addition to HTS, many other Syrian militias are fighting with their own agendas and allegiances.
One major coalition group taking part in the offensive on Aleppo is the Syrian National Army (SNA), an umbrella group established in 2017 that brings together dozens of factions with varying ideologies.
In contrast to the more centralized and cohesive Hayat Tahrir al-Sham, the SNA is a fragmented coalition of disparate armed groups. Many previously operated under the Free Syrian Army, and have often clashed among themselves.
Despite its internal divisions, many SNA factions maintain strong ties to Turkey. Some, such as the Sultan Suleiman Shah Brigade, the al-Hamza Division, and the Sultan Murad Brigade, are closely aligned with Ankara, reflecting their Turkish backing through names honoring Ottoman figures.
However, not all SNA factions align fully with Turkish interests. Certain groups, while cooperating with Ankara, seek to balance their own priorities. For instance, the coalition includes influential rebel factions like Ahrar al-Sham, whose stated goals are to “overthrow the Assad regime” and “establish an Islamic state governed by Sharia law.”
In the past few days, SNA forces have clashed with Kurdish forces in northern provinces and taken several strategic towns and villages. This move is aligned with one of Turkey’s main goals in Syria: preventing the presence of a powerful Kurdish military and organizations along Turkish-Syrian border.
The Syrian Democratic Forces (SDF) are a coalition of primarily Kurdish fighters, alongside Arabs and other ethnic groups, that have emerged during Syria’s civil war.
Formed in 2015, the SDF operates under the leadership of the Kurdish People’s Protection Units (YPG) and has received significant support from the US, particularly in the campaign against “Islamic State.”
After “Islamic State” was largely defeated, the Kurdish-led forces consolidated control over towns in the northeast, expanding an autonomous region they had built there.
However, Kurdish fighters still contend with their longtime enemy, Turkey, which sees them as an extension of a Kurdish separatist insurgency and the Kurdistan Workers’ Party (PKK).
Like other regional powers, Turkey has exerted its influence in Syria by backing armed groups such as HTS and SNA. Since the beginning of the civil war, the Turkish military has launched several military interventions across the border into Syria, mostly against Syrian Kurdish-led forces.
Its latest operation dates back to October 2019, with Ankara’s goal being to push Kurdish fighters at least 30 kilometers (about 19 miles) away from its border and establish a so-called “safe zone” in parts of Syria that it plans to send refugees. 
Since then, Turkey has effectively controlled a zone along Syria’s northern border, enabling it to begin coordinating with anti-Assad rebel groups.
Russia has been Assad’s most reliable ally, providing military and logistical support throughout the war. Moscow’s airstrikes and troops helped Assad maintain power for years, but its capacity to intervene has diminished as resources have been diverted to the war in Ukraine.
Iran views Syria as a vital link in its “axis of resistance,” a coalition of militias in the Middle East that fight against US influence and Israel. It has supported Assad by deploying Iranian forces and Hezbollah militants as Damascus allowed the flow of weapons from Iran and Iraq into Lebanon.
However, recent reports have suggested Iran is pulling back its personnel, indicating challenges in maintaining its role amid Assad’s fall.
The US initially supported opposition groups during the early stages of the uprising in the 2010s, later shifting focus to fighting “Islamic State.”
Today, about 900 US troops remain in Syria, primarily in Kurdish-controlled areas and oil-rich regions in the northeast, as well as at a military outpost in the border zone between Syria, Iraq and Jordan.
Over the past decade, Israel has routinely targeted Iranian and Hezbollah assets in Syria through frequent airstrikes. Its actions aim to disrupt weapons transfers to Hezbollah and neutralize threats near the Israeli-occupied Golan Heights.
Recently, Israeli forces moved into Quneitra, a border town near the Golan Heights, as militant groups gained control of surrounding areas. The Israeli military has declared new military zones in the Golan Heights along the border with Syria.
Edited by: Helen Whittle