Syria has been wracked since March 15, 2011, by a devastating civil war.
It erupted after the repression of peaceful pro-reform protests prompted an armed uprising against President Bashar al-Assad's regime, and has since become many-sided.
2011: Revolt and repression
March 15: unprecedented protests demanding greater civil liberties and freedom for political prisoners erupt after 40 years of iron-fisted rule by the Assad family.
Crackdowns in Damascus, Banias and Daraa, cradle of the uprising, where 100 people are reportedly killed on the 23rd. The regime denounces "an armed rebellion by Salafist groups", while Britain, France and the United States denounce the crackdown.
In April, protests spread, with calls for the Assad regime's fall.
2012: All-out war
July 17: Moderate fighters from the Free Syrian Army (FSA) launch a battle for Damascus, but the government has held on firmly while rebels have surrounded the capital.
July 20: Rebels launch an offensive in the northern city of Aleppo, which has since been divided between areas in the east occupied by rebels and regime forces in the west.
In August, heavy weaponry is brought into play, including warplanes.
2013: Chemical weapons
June 5: The Syrian army recaptures the key border town of Qusayr, in an assault led by fighters from Lebanon's powerful Shiite movement Hezbollah.
The battle stokes sectarian tensions, the regime being dominated by the Alawite minority, a branch of Shiite Islam, while Syria is Sunni majority. Rebels go on to lose numerous strongholds.
August 21: the regime is accused of killing more than 1,400 people, according to the United States, with chemical weapons in two rebel-held zones near Damascus.
In September, Washington and Russia agree on a plan to eliminate Syria's chemical weapons, ruling out the threat of US strikes, made after the chemical weapons attacks.
2014: Rise of the jihadists
The jihadist Islamic State group, which emerged in the Syrian conflict in 2013, quickly gains ground, seizing vast swathes of territory in the northeast and overshadowing the anti-regime rebellion.
IS makes Raqa city the "capital" of its caliphate, which it proclaims in late June in territories it controls in Syria and Iraq and where it imposes a harsh interpretation of Islamic law.
The group claims numerous "executions", including of Western hostages.
From 2013 jihadists, notably from the Al-Qaeda-affiliated Al-Nusra Front, had strengthened their grip on the north, to the detriment of the FSA.
2015: Kobane retaken
January 26: Kurdish forces backed by US-led air strikes drive IS out of Kobane on the border with Turkey, after more than four months of fierce fighting.
February: Hezbollah, Iranian officers and the Syrian army seize strategic posts on the edge of the Golan Heights held by Israel during their biggest offensive in southern Syria.