The conflict in Syria has entered its fifth year, a grim anniversary in what has become the worst humanitarian crisis of our time.
It began on March 15, 2011 when the Syrian government met mostly peaceful protests in several towns and cities with gunfire, beatings and arrest. Eventually, the opposition acquired weapons, soldiers defected, and the uprising transformed into a grinding civil war with ugly sectarian dimensions that sucked in countries across the region and further afield. An estimated 220,000 people have now been killed and life expectancy has dropped two decades to 55 years, according to the United Nations. 3.9 million people have fled the country, and a further 7.6 million have been internally displaced.
Syria's economy has collapsed and 80 percent of the country now lives in poverty. Half of all school-aged children haven't attended school in three years. The country has literally gone dark, with 83 percent of electricity supplies now cut.
A peaceful solution to the conflict now seems further away than ever, and United Nations Security Council (UNSC) resolutions aimed at pushing President Bashar al-Assad to step down or cease attacking his own people are consistently vetoed by his longtime allies Russia and China. Moderate rebel factions fighting for a democratic system have lost out to Islamist-linked groups and the chaos has allowed extremist militants such as the so-called Islamic State (IS) to seize territory and power.
Arab Spring-inspired unrest begins after police arrest fifteen young boys in southern town of Daraa for spray-painting "the people want the downfall of the regime" on buildings. Large demonstrations take place in Damascus, Daraa and elsewhere to demand the release of political prisoners and Assad's resignation.
Unrest spreads and protests continue, including in Homs and Banyas. Some pro-government demonstrations take place too. Security forces attempt to crush dissent, killing dozens. Assad blames foreign powers for the unrest, and announces measures designed to placate protesters, including allowing new political parties and a potential end to a state of emergency that has been in place for 48 years. Opposition members say the measures are superficial and don't constitute meaningful reform.
Protests demanding Assad's ouster spread further. The government's response becomes more brutal and Assad vows to destroy what he describes as "terrorists." Hundreds are killed, including more than 120 at "Bloody Friday" protests in Daraa, Damascus and elsewhere. The United States and France condemn the crackdown and call on Assad to implement reforms.
In an attempt to calm unrest, the government releases some political prisoners and repeals the emergency law. The first Syrian refugees cross into Turkey, where authorities build the first of 20 Syrian refugee camps to provide them with shelter.
Syrian army tanks are deployed in Daraa, Homs, Banyas and the Damascus suburbs in an attempt to put down the protests.
The US imposes sanctions on both Assad and senior Syrian government officials, while the European Union implements an arms embargo alongside an asset freeze and travel ban on senior officials.
Reports emerge of Iran providing assistance and equipment to help quell the uprising. Tehran later provides arms and combat troops to bolster Assad.
The crackdown continues, including 34 killed at huge anti-government demonstration in Hama. The Arab League condemns the Syrian government's actions.
More than 120 soldiers are killed in Jisr al-Shughour by what Damascus describes as "armed gangs," but some reports suggest the attack was carried out by defected members of the security forces and local residents. The army besieges the city and thousands of civilians leave their homes and seek refuge in Turkey.
The burgeoning conflict spills over into Lebanon as pro and anti-Syrian government factions clash in Tripoli. Assad pledges to start a "national dialogue" on reform.
After a massive demonstration in Hama, Assad removes the provincial governor from power and deploys troops. Hundreds are reported killed in the city.
The government holds a national dialogue, which is boycotted by opposition groups. The US says Assad has "lost legitimacy".
Military defectors announce the formation of the Free Syrian Arm (FSA) headed by Riad Al-Asaad, a former Syrian army colonel.
International condemnation grows. The UK, US, European Union and others demand that Assad steps down. The UN condemns human rights violations and the use of force against civilians. Saudi, Bahrain and Kuwait recall ambassadors.
Formation of the Syrian National Council in Istanbul, a coalition of groups in and outside the country opposed to Assad.
The European Union bans oil imports from Syria following the US's decision to do the same the previous month. Turkey, a former ally of Assad, cuts contact with Syrian authorities. Fighting between the Syrian military and defected troops continues.
The UN Security Council (UNSC) attempts to pass a resolution condemning Assad's government. Russia and China veto it. Meanwhile, UN High Commissioner for Human Rights Navi Pillay says the crisis shows signs of "descending into an armed struggle." Clashes take place in Homs and government troops shell the city.
The Arab League announces a peace plan. Damascus accepts but does not adhere. The Arab League take the unprecedented step of suspending Syria and imposes sanctions.
The FSA attacks a military base near Damascus, in the highest profile assault yet. Pro-government Syrians attack foreign embassies.