Explained: What led to Bashar al-Assad's downfall in Syria
What's the story
The Assad family's five-decade rule in Syria came to an end as rebels captured Damascus.
The rapid advance came after a 13-year civil war, with the opposition capturing Syria's second-largest city, Aleppo, in a surprise operation.
The Syrian army was weakened by low morale and a lack of resources, worsened by corruption and looting.
Assad's key allies Iran and Hezbollah were weakened by conflicts with Israel while Russia was distracted by its military operations in Ukraine.
Rebel advance
Rebel coalition's role in al-Assad's downfall
The rebel advance was led by the Hayat Tahrir al-Sham (HTS) coalition, which evolved from the Nusra Front—an early al-Qaeda affiliate in Syria.
The group rebranded itself as HTS under leader Ahmed al-Sharaa, aka Abu Mohammed al-Jawlani.
The Turkey-backed Syrian National Army (SNA) also contributed significantly to the operation.
Despite being a key supporter of the Syrian opposition, Turkey did not officially endorse the recent offensive.
Allies's distraction
Al-Assad's allies distracted by regional conflicts
Al-Assad's military support from Russia and Iran also dwindled as both countries grappled with other regional conflicts.
In this regard, Russia's airstrikes failed to prevent rebel advances as it focused on Ukraine.
Iran's involvement was also hampered by its conflict with Israel and Hezbollah's losses in Lebanon.
Hezbollah, which had supported al-Assad since 2013, suffered heavy casualties in recent conflicts with Israel.
Israeli Prime Minister Benjamin Netanyahu attributed al-Assad's downfall to "blows we have inflicted on Iran and Hezbollah."
Military weakness
Al-Assad's military weakened by corruption and looting
Al0Assad's army was crippled by rampant corruption and looting, with tanks and planes running out of fuel.
An army source told Reuters that army morale had plummeted over the last two years.
The HTS-led coalition was more coherent and stronger than any other rebel group in the war.
"After they lost Aleppo like that, regime forces never recovered and the more the rebels advanced, the weaker Assad's army got," Aron Lund from Century International told Reuters.
Turkey's position
Turkey's stance on the Syrian opposition
Turkey had long been a key backer of the Syrian opposition but did not formally support the latest offensive.
Turkish Foreign Minister Hakan Fidan admitted Turkey "knew something was coming" after failed attempts to bring Assad to the negotiating table.
A Turkish official said HTS "does not receive orders or direction from us."
Despite seeing HTS as a terrorist group, Turkey keeps forces in northwest Syria and provides support to some rebels intending to join, like SNA.