The conflict has left half a million people dead since 2011 and displaced millions more. It has divided the country into several zones of influence with the warring parties backed by different foreign powers.

- Revolt to repression -

Protests erupt in Syria in March 2011 at the height of the Arab Spring uprisings, after four decades of repressive rule by the Assad dynasty,

The government of President Bashar al-Assad, who succeeded his father Hafez in 2000, cracks down violently on the demonstrators.

An armed rebellion is launched with support from Turkey, the West and some Arab countries.

The Free Syrian Army (FSA) rebels seize large swathes of territory, including the centre of third city Homs and a chunk of second city Aleppo.

- Iran, Hezbollah -

The same year, Iran-backed Lebanese Shiite militant group Hezbollah deploys fighters to back the Syrian government. Iran also provides support to Assad.

- Gas attacks -

In August 2013, a chemical attack on two rebel-held areas near Damascus kills more than 1,000 people, according to the US. The Syrian government denies responsibility.

In November 2023, France issues an international arrest warrant for Assad, suspected of complicity in the attacks.

- IS rise and fall -

The jihadist Islamic State group (IS) proclaims a "caliphate" in parts of Syria and Iraq in June 2014.

In September 2014, a US-led coalition launches air strikes against IS.

The jihadists are eventually ousted from their last territory in Syria by US-backed Kurdish-led fighters in 2019.

- Russia rescues Assad -

Syria's main ally Russia launches a campaign of air strikes on rebel-held areas in September 2015, marking a turning point in the war.

Russia's intervention helps Assad's forces to retake key rebel bastions, from Aleppo in 2016 to the eastern outskirts of the capital Damascus in 2018.

- Ceasefire, and bombardments -

The Syrian government launches an offensive in December 2019 to retake the northwestern province of Idlib, the last major rebel bastion in Syria.

Russia and Turkey broker a ceasefire in March 2020 after months of fighting.

However there are sporadic bombardments, which leave more than 3,800 dead in 2021 and a similar number in 2022.

- IS still active -

In January 2022, IS fighters attack a Kurdish-controlled prison in the northeast to try to free jailed jihadists. Hundreds are killed in the week-long assault.

- Turkish operations -

Turkey in November 2022 launches a fourth operation against Kurdish forces in northern Syria.

Erdogan forges closer ties with Damascus.

- Back in the Arab League -

On May 7, 2023, Syria comes out of its diplomatic isolation, rejoining the Arab League from which it had been expelled in 2011. Washington protests.

- Israeli strikes -

Amid the war in Lebanon between September 2024 and the November ceasefire, Israel carries out repeated strikes in Syria, saying it wants to prevent Hezbollah from "transferring" arms to Lebanon.

- Lightning rebel offensive -

On November 27, rebel forces, led by the Islamist group Hayat Tahrir al-Sham (HTS,) launch an offensive against Assad's troops.

They capture most of Aleppo and then, on Thursday, the central city of Hama.