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.
21 January 2015: Syrian men carry injured victims following a reported air strike on the besieged rebel-held town of Douma, northeast of the capital DamascusSameer al-Doumy/AFP28 January 2015: A Kurdish man checks the eastern part of the Syrian border town of Kobane, known as Ain al-Arab. Kurdish forces recaptured the strategic town on the Turkish frontier from Islamic State on 26 JanuaryBulent Kilic/AFP30 January 2015: A wounded fighter from the Suqour al-Sham Brigade, which is part of the Free Syrian Army, uses his weapon as a crutch as he limps during what activists said were clashes with forces of Syria's President Bashar al-Assad, in the al-Arbaeen mountain area of western IdlibKhalil Ashawi/Reuters2 February 2015: A man gives medical assistance to an injured man as two wounded children wait nearby at a field hospital after what activists said was an air strike by forces of Syria's President Bashar al-Assad in the Douma neighbourhood of DamascusMohammed Badra/Reuters4 February 2015: A rebel fighter holds a position in al-Mayasat, a rebel-controlled area near the industrial zone of the northern Syrian city of AleppoZein al-Rifai/AFP9 February 2015: A boy stands on rubble as people try to put out a fire after what activists said were air strikes followed by shelling by forces loyal to Syria's President Bashar al-Assad in the rebel-held Douma neighbourhood of DamascusMohammed Badra /Reuters13 February 2015: A Syrian child sits in the back of a truck loaded with furniture as residents collect what's left of their belongings from their apartments following months of shelling by regime forces in the besieged rebel held area of Douma, north east of the capital DamascusSameer al-Doumy/AFP2 March 2015: Pupils attend the first day of school in Kobane, also known as Ain al-Arab, as they returned to class after Kurdish and rebel forces expelled Islamic State jihadists from the town following more than four months of fightingMichalis Karagiannis/AFP6 March 2015: A view of a damaged street with sandbags used as barriers in Aleppo's Saif al-Dawla districtHosam Katan/Reuters8 March 2015: Smoke rises after what activists said were air strikes by forces loyal to Syria's President Bashar al-Assad in Arbeen, in the eastern Damascus suburb of GhoutaDiaa Al-Din/Reuters18 March 2015: Rebel fighters from the Suqour al-Sham Brigade prepare a locally-made shell before launching it towards forces loyal to Syria's president Bashar Al-Assad in countryside around IdlibMohamad Bayoush/Reuters20 March 2015: A man carries an injured man after what activists said was shelling from forces loyal to Syria's President Bashar al-Assad in Aleppo's Al-Mashad neighbourhoodSultan Kitaz/Reuters21 March 2015: Residents walk near upright buses that serve as protection from snipers loyal to Syria's President Bashar al-Assad, in Aleppo's rebel-controlled Bustan al-Qasr neighbourhoodAmmar Abdullah/Reuters22 March 2015: Kurdish men sit near bonfire near a destroyed building, in the town of Kobane, also known as Ain al-ArabYasin Akgul/AFP23 March 2015: A rebel fighter looks inside a weapon on the frontline outside Idlib in northern SyriaKhalil Ashawi/Reuters24 March 2015: Rebel fighters from the Ahrar al-Sham Islamic Movement sit inside an armoured vehicle during what they said was an offensive to take the city of IdlibKhalil Ashawi/Reuters25 March 2015: A Kurdish Syrian woman walks with her child past the ruins of the town of KobaneYasin Akgul/AFP25 March 2015: A female Syrian soldier from the Republican Guard commando battalion drives a tank during clashes with rebels in the Jobar area of eastern DamascusJoseph Eid/AFP28 March 2015: Young boys play on a destroyed building in the Syrian town of Kobane, also known as Ain al-ArabYasin Akgul/AFP21 April 2015: A rebel fighter fires his weapon at the frontline during a battle to unite rebel factions against forces loyal to Syria's President Bashar al-Assad in Jobar, a suburb of DamascusAmer Almohibany/Reuters23 April 2015: An aerial view of Seif El Dawla neighbourhood in Aleppo and the Aleppo International Stadium, controlled by forces loyal to Syria's president Bashar Al-AssadHosam Katan/Reuters6 May 2015: Ghazal, 4, and Judy, 7, carrying eight-month-old Suhair, react after what activists said was shelling by forces loyal to Syria's President Bashar al-Assad near the Syrian Arab Red Crescent centre in the Douma neighborhood of DamascusBassam Khabieh/Reuters12 May 2015: A rebel fighter with blood on his forehead sits in a trench during an offensive to take control of al-Mastouma military camp near Idlib from forces loyal to Syria's President Bashar al-AssadKhalil Ashawi/Reuters13 May 2015: Residents return to their villages on a pickup truck after Kurdish People's Protection Units (YPG) fighters said that they retook control of the countryside around Ras al-Ain from Islamic StateRodi Said/Reuters19 May 2015: Explosives are detonated by Syrian government forces inside a tunnel that was reportedly used by rebels in the northern Syrian city of AleppoGeorge Ouralian/AFP29 May 2015: A member of al-Qaeda's Nusra Front takes down a picture of Syria's President Bashar al-Assad in the northwestern city of Ariha, after a coalition of insurgent groups seized the area in Idlib provinceAmmar Abdullah/Reuters3 June 2015: A man holds a baby who survived what activists said was a barrel bomb dropped by forces loyal to Syrian President Bashar al-Assad at the old city of AleppoAbdalrhman Ismail/Reuters3 June 2015: Shrapnel damage is seen at the souk of the old city of HomsOmar Sanadiki/Reuters13 June 2015: Islamic State fighters laugh as they herd people away from the Turkish border crossingBulent Kilic/AFP14 June 2015: A Syrian child fleeing the war is lifted over fences at the Turkish border crossing at AkcakaleBulent Kilic/AFP15 June 2015: Kurdish fighters gesture while carrying their parties' flags in Tel Abyad, Raqqa governorate, after they took control of the town on the Turkish border from Islamic StateRodi Said/Reuters6 JULY 2015: A Free Syrian Army fighter carries a copy of the Koran as he walks along a street in Jobar, a suburb of DamascusBassam Khabieh/Reuters12 July 2015: Boys play with a pipe, pretending it is a mortar, at a site hit by what activists said was a barrel bomb dropped by forces loyal to Syria's President Bashar al-Assad in the old city of AleppoAbdalrhman Ismail/Reuters22 August 2015: A wounded Syrian girl looks on at a makeshift hospital in the rebel-held area of Douma, east of the capital Damascus, following shelling and air raids by Syrian government forcesAbd Doumany/AFP24 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