The Syrian conflict has lasted nearly five years, killing more than 300,000 people and displacing millions. There are actually two wars going on in Syria. First came the rebellion against Syrian President Bashar Assad, who succeeded his father as authoritarian leader of Syria in 2000. He responded to peaceful Arab Spring protesters in 2011 with a crackdown so brutal that it sparked an armed revolt that still rages. Russia and Iran have been Assad's main allies in the conflict, while Saudi Arabia, other Gulf Arab states and Western powers have supported insurgents fighting to overthrow him.
Then came an invasion by the Islamic State (also known as Isis or Daesh), which Assad considers one of many "terrorist" groups arrayed against him. Formerly known as al-Qaida in Iraq, Isis is infamous for videotaped beheadings, mass murder and systematic rape of captive women – and now, inspiring or possibly directing attacks in the West. Syria's chaotic war opened the way for Isis (Daesh) to expand across the border in 2013. IS has seized about a third of Syria, and has placed its capital in the northern Syrian city of Raqqa. Syrian Kurds are fighting Daesh on the ground and have recaptured wide areas of northern Syria. A US-led coalition is fighting Isis from the air, while the CIA is secretly arming and assisting rebels fighting Assad.
In this gallery IBTimes UK looks back at another bloody year in the Syrian conflict, as it drags on with no end in sight.
24 August 2015: A boy runs away from a site hit by what activists said were airstrikes by forces loyal to Syria's President Bashar al-Assad in the Douma neighbourhood of DamascusBassam Khabieh/Reuters11 December 2015: Damaged buildings are pictured at night in Aleppo, SyriaAmmar Abdullah/Reuters8 December 2015: A baby lies in a neonatal unit in a field hospital in the Douma neighbourhood of DamascusBassam Khabieh/Reuters19 November 2015: Doctors treat an injured civilian in a field hospital after what activists said was shelling by forces of Syria's President Bashar al-Assad in the Douma neighbourhood of DamascusBassam Khabieh/Reuters18 November 2015: A wounded Syrian boy cries at a makeshift hospital following a reported air strike by government forces in the rebel-held area of Douma, east of the capital DamascusAbd Doumany/AFP5 November 2015: A resident rides his bicycle near what appears to be an exploded cluster bomb shell in the town of Douma, eastern Ghouta in DamascusBassam Khabieh/Reuters29 October 2015: A rainbow is seen as residents inspect a site damage from what activists said was an airstrike by forces loyal to Syria's President Bashar al-Assad on the main field hospital in the town of Douma, eastern Ghouta in DamascusBassam Khabieh/Reuters10 November 2015: Kurdish female troops from the Syrian Democratic Forces stand in a forward operating base overlooking the frontline near the Isis-held town of HoleJohn Moore/Getty Images23 October 2015: A groom holds his bride's hand as they pose near a mortar and damaged buildings before heading to their wedding ceremony in the town of Kobani. The couple was the first to have a civil marriage after the town was captured from Islamic State by Kurdish-led forcesRodi Said/Reuters1 October 2015: Forces loyal to Syria's President Bashar al-Assad clash with the Army of Islam fighters, on the eastern mountains of Qalamoun overlooking the town of Douma, eastern Ghouta, near DamascusBassam Khabieh/Reuters25 August 2015: An image distributed by Islamic State militants on social media purports to show the destruction of the Roman-era Baal Shamin temple in the ancient Syrian city of PalmyraReuters13 December 2015: The sister of Mohammed Ismael, who died in one of three suicide car bombings claimed by Islamic State group in the town of Tal Tam, mourns during his funeral in Qamishli, a Kurdish-majority city in Syria's northeastern Hasakeh provinceDelil Souleiman/AFP20 December 2015: A resident inspects a site that was hit by an Israeli strike, killing a Lebanese militant leader Samir Qantar, in the district of Jaramana, DamascusOmar Sanadiki/Reuters