2011:
March 15: Unprecedented protests inspired by the Arab Spring erupt, demanding reform after 40 years of iron-fisted rule by President Bashar al-Assad's family.
- Security forces crack down on protesters in Damascus and Daraa, known as "the cradle of the uprising", where 100 people are reportedly killed on March 23.
- The regime claims it is cracking down on "an armed rebellion" by radical Islamists, while Britain, France and the United States denounce the repression.
- Protests spread, with demonstrators calling for Assad's ouster.
2012:
July 17: Moderate rebels from the Free Syrian Army declare that the battle for Damascus has begun, but the government holds its ground.
- July 19: Rebels launch an offensive in the northern city of Aleppo, which has since been divided between rebel-held neighbourhoods in the east and regime-held districts in the west.
2013:
April 30: Hassan Nasrallah, chief of the powerful Lebanese Shiite group Hezbollah, acknowledges that his troops are fighting in Syria in support of Assad.
- August 21: Hundreds of people are killed in chemical weapons attacks targeting rebel bastions near Damascus. The West accuses Assad's regime.
- In September, the United States and Russia agree on a plan to eliminate Syria's chemical weapons, narrowly heading off US strikes.
- 2014
January 14: The jihadist Islamic State group, which emerged in Syria in 2013, seizes Raqa, the first provincial capital to fall out of regime control.
- June 29: IS declares the establishment of an Islamic "caliphate". It later claims numerous murders, including of Western hostages.
- September 23: The US and Arab allies launch air strikes on IS in Syria.
- May 9: Syrian troops recapture the Old City of Homs, after a two-year siege and near-daily bombardment. Rebels withdraw.
2015
January 26: Kurdish forces backed by US-led air strikes drive IS out of the flashpoint town of Kobane on the Turkish border, after months of fierce fighting.
- March 28: Syria's Al-Qaeda affiliate, Al-Nusra Front, backed by rebel allies, seizes most of the northwestern city of Idlib, the second provincial capital after Raqa to fall out of government hands.
- In May Assad says that such setbacks do not mean the conflict is lost, but in July he acknowledges the shrinking ranks of his army.
- September 30: Russia launches air strikes on Syria, saying it is targeting "terrorists" including IS, but it faces accusations of hitting non-jihadist rebels and civilians as it seeks to bolster Assad.
2016
February 27: An unprecedented "cessation of hostilities" comes into force. It applies to combat zones between Russian-backed regime forces and non-jihadist rebels, but does not apply to the more than half of the country's territory that is controlled by extremist groups.
