Islamic State (IS, formerly ISIL) 21 May announced it had seized “full control” of ancient city Palmyra in central Syria; govt forces retreated following clashes with IS outside Palmyra 14 May. Rebels escalated campaign against remaining regime strongholds in Idlib province; coalition of rebel forces including Ahrar al-Sham and Jabhat al-Nusra (JN) captured Mastoumeh village 19 May and Ariha 28 May. Regime counter-offensive launched in Idlib following 25 April rebel victory in Jisr al-Shaghour made little headway. Regime forces 3 May escalated offensive in Ghouta suburbs of Damascus; heavy fighting between rebels and govt forces reported in Maydaa, key supply route into eastern Ghouta. Fierce clashes between IS and regime forces began 6 May in city of Deir az-Zour, eastern Syria. Clashes in Qalamoun border region ongoing (see Lebanon). U.S. special forces 15-16 May mounted raid in eastern Syria near al-Omar oil field, killing IS commander Abu Sayyaf and capturing his wife; dozen militants reportedly killed in raid. U.S. military 3 May denied reports that coalition airstrikes 30 April-1 May killed 52 civilians in Birmahle village, Aleppo province, said those killed were fighters. UN 5 May announced launch of renewed peace talks in Geneva, billed as “low-key consultations” expected to last four-six weeks; 30 armed opposition groups declined invitation to join talks. IS 22 May seized last govt-controlled Iraq-Syria border crossing al-Tanf in Homs province.

Islamic State (IS, formerly ISIL) 1 April captured large areas of Yarmouk camp in southern Damascus in cooperation with al-Qaeda-linked Jabhat al-Nusra (JN). Regime responded with military campaign against IS including aerial bombings 8 April; IS reportedly withdrew from much of camp by 14 April, leaving JN as main rebel force in Yarmouk. Rebels continued expansion in south Daraa province after late-March gains in Busra al-sham; Southern Front rebels 2 April captured Nasib border crossing at Syria-Jordan border. Tension erupted between rebel groups as JN attempted to establish presence at Nasib; Southern Front 15 April announced they will not co-operate militarily with JN, publicly disassociating themselves from group. Coalition of rebel forces consolidated control in Idlib province, NW Syria, after late-March capture of provincial capital; 25 April seized control of Jisr al-Shughour as campaign to capture remaining regime holdings in province continued. JN confirmed death of local commander in Marea, in 7 April car bombing in N Aleppo, reportedly attributed to IS. Local media 10 April reported IS holding 50 civilian hostages following 31 March raid on Mabujeh village, Hama province. Clashes in Qalamoun region ongoing; 30 rebels and twelve IS fighters reported killed 21-22 April. Rebels including JN attacked govt intelligence centre in Aleppo 13-14 April; thirteen militants reported killed, twenty regime forces killed/wounded. Deadly regime shelling continued including 16, 22 April strikes in areas around Damascus. 6 April Russia-facilitated talks between Syrian govt representatives and low-profile opposition figures ended without notable result. Israel reportedly carried out raids in Qalamoun, including on Hizbollah arms convoy 22 April (see Lebanon), missile depot 23 April.

As country entered fifth year of conflict, ongoing offensives by regime and allied forces against rebels yielding mixed results. Regime campaign backed by Hizbollah and Iran aiming to reverse months of rebel gains in south slowed, but pro-regime forces maintain control of newly-gained territory SW of Damascus. Offensive on rebel-held areas north of Aleppo continued: regime forces suffered heavy casualties, dozens of fighters captured; lost most of the ground seized in 16 Feb attack. Following relative success against regime, rebel confidence in Aleppo further boosted by signs of weakness among Islamic State (IS, formerly ISIL) forces east of city, following string of IS losses in Kurdish areas surrounding Kobani at hands of Turkish Armed Forces (PYD) and rebels. U.S.-led coalition airstrikes against IS also continued: five airstrikes hit IS positions in Kobani and Raqqah 25-26 March. Al-Qaeda-linked Jabhat al-Nusra (JN) continued expansion west of Aleppo, following capture late-Feb of last-remaining stronghold of Western-backed rebel group Haraket Hazm, which disbanded itself 1 March after JN defeat and issued statement suggesting remaining members will join Levant Front, leading alliance of non-jihadi rebels in Aleppo. Hazm’s defeat leaves U.S. without clear partner in northern Syria. Amid continued efforts to broker “freeze” of Aleppo fighting, rebels reiterated refusal to work with UN Syria Envoy de Mistura. Coalition of rebels 24 March launched major offensive to capture NW city of Idlib from govt; succeeded in doing so within five days. Rebels 25 March captured historic town Busra al-Sham in Daraa province, south.

Regime and allied forces early Feb began major campaign in south following months of rebel gains in Daraa and Quneitra provinces: retook some ground from rebels including areas south-west of Damascus, scores reported killed by mid-month; pro-regime media reported direct Iranian, Hizbollah participation, signalling apparent major escalation by non-Syrian pro-regime forces in south. Regime and allied forces 16 Feb launched attack on rebel-held areas north of Aleppo and inside city: captured some ground but suffered heavy casualties; hundreds of rebels and pro-regime forces reported killed. UN Syria Envoy de Mistura 17 Feb briefed UNSC on efforts to broker “freeze” of Aleppo fighting: said regime indicated willingness to halt aerial bombardments for six weeks while pursuing agreement on “freeze” in part of Aleppo. Announcement made without rebel agreement to halt fighting; rebel scepticism of UN efforts increased following de Mistura’s 13 Feb statement that Bashar Assad is “part of the solution”, later clarified to mean Assad needed for “de-escalation of violence”. Kurdish forces and allied rebels continued advancing following late Jan victory over Islamic State (IS, formerly ISIL) in Kobani: seized several mostly Kurdish towns south of city, late Feb seized north-eastern town Tel Hamis. IS late Feb reportedly abducted over 200 Christian villagers in north east. Deadly regime airstrikes continued including scores killed around Damascus 5 Feb following rebel shelling of regime-held areas. U.S.-led coalition airstrikes against IS continued; at least 30 reported killed in Raqqah province 6 Feb.

Early-Jan winter storm slowed military activity but added to hardships endured by millions of people in need of humanitarian assistance: UN Office for Coordination of Humanitarian Affairs (OCHA) announced winter response plan underfunded by $70mn; World Food Program said $112mn urgently needed to cover food assistance for coming four months. Military activity increased as storm subsided: al-Qaeda-linked Jabhat al-Nusra (JN) launched offensive to capture sole remaining regime base in south-eastern Idlib countryside, Abu al-Duhr airbase; 13 Jan captured neighbouring Tal Salmo town from regime forces, 18 Jan claimed downing of regime cargo plane killing 35. Kurdish forces late month pushed Islamic State (IS, formerly ISIL) forces out of Kobani amid continued U.S.-led airstrikes. At least eighteen reported killed in rare clashes between regime and Kurdish forces controlling separate parts of Hasakeh city 17-18 Jan. Deadly regime airstrikes continued including scores killed in IS-held area of Hasakeh province 20 Jan, scores more in rebel-held area near Damascus 23 Jan. Russia failed to convince significant opposition figures to attend late Jan talks with regime representatives in Moscow; Damascus signalled lack of interest by lowering level of representation at talks.

Al-Qaeda-linked Jabhat al-Nusra (JN) continued to advance in Idlib province following Nov expulsion of forces loyal to U.S. and Saudi-backed rebel commander Jamal Marouf from stronghold in Jabal al-Zawiya region: most recipients of U.S. support either evicted from province, disarmed, subordinated to JN or forced to seek protection from Islamist group Ahrar al-Sham (AS) by early Dec; U.S. cut support to groups in Idlib and neighbouring Hama province as JN advance left remaining U.S. allies unable to guarantee safety of supply lines. JN, AS mid-month captured two regime bases in southern Idlib after over eighteen months of attempts by U.S.-backed rebels; around 180 killed according to Syrian Observatory for Human Rights (SOHR) NGO. Former recipients of U.S. support joined Idlib operation, resulting in U.S.-supplied arms being employed under JN leadership. Mainstream rebel alliance “Revolutionary Command Council” (RCC), covering broad array of rebel factions including U.S.-backed groups and AS, took further steps toward forming representative umbrella organisation; RCC president Qais Abdullah Sheikh early Dec met UN Syria envoy De Mistura in Turkey along with other rebel leaders following late Nov RCC election. Clashes between regime, Islamic State (IS, formerly ISIL) continued: scores reported killed in IS attacks on military base in Deir az-Zour province. Mass grave reportedly discovered in east mid-month containing hundreds of members of Sheitat tribe, executed by IS. Deadly regime airstrikes continued including scores reported killed around Homs city 17 Dec.

UN Syria envoy Staffan de Mistura early Nov launched initiative to establish “freeze” in battle between regime and opposition in Aleppo. Observers predicted low chance of success: regime described as lacking incentives for deal, seeing status quo as beneficial; initiative criticised by opposition, citing tendency of past local ceasefires to benefit regime by cementing military victories, freeing up resources for advances on other fronts. Syrian FM Moallem 27 Nov claimed govt, Russia, both supporting proposal. Deadly regime airstrikes continued in Aleppo city, including at least twenty civilians reported killed in rebel-held areas 6 Nov; at least 21 reported killed in town held by Islamic State (IS, formerly ISIL) north east of city 9 Nov. Al-Qaeda (AQ)-linked Jabhat al-Nusra advanced in fight against other rebels, including Western-backed Syrian Revolutionary Front: early month reportedly captured several towns and villages in Idlib province, including Deir Sinbel and Khan al-Subul 1-2 Nov. Rebels continued advancing in south; observers described strategic impact as limited in absence of U.S. decision to increase cross-border flow of arms from Jordan. U.S.-led air-strikes targeting IS and AQ-linked militants continued: Syrian Observatory for Human Rights NGO 22 Nov said 910 killed, including 52 civilians, in coalition airstrikes since beginning of campaign late Oct; at least 50 militants reported killed in clashes, air-strikes in Kurdish city of Kobani 29-30 Nov. Almost 100 reported killed in regime air-strikes on IS-held Raqqah city 25 Nov.

U.S.-led airstrikes expanded despite continued lack of coherent strategy; over 500 jihadis, dozens of civilians reported killed since late Sept. U.S. mid-month increased air support for Kurdish forces, anti-regime rebels defending Kurdish city of Kobani after media uproar over attempts by Islamic State (IS; formerly ISIL) militants to capture city; U.S. failed to strike IS fighters heading to Kobani in preceding days, downplayed battle’s importance. U.S. escalated pressure on Turkey to increase cooperation with anti-IS coalition; Turkey resisted, citing need for U.S. to address continued rule of President Assad. Turkey renewed calls for no-fly zone in northern Syria, blocked fighters and weapons from crossing border to assist Kurdish forces in Kobani before allowing up to 200 Kurdish peshmerga fighters equipped with heavy weapons to travel from northern Iraq to Kobani late month. U.S. commitment of resources toward moderate rebels remained limited despite rhetoric; rebels complained of inability to launch offensives against IS without increased U.S. support for fight against regime. Regime bombardment of anti-IS rebels continued in support of advances in Aleppo and Damascus suburbs; dozens reported killed in bombing of IDP camp in Idlib province 29 Oct. Regime 23 Oct recaptured central town of Morek in Hama province. Clashes between regime and IS fighters continued including scores reported killed in IS attack on regime-held gas field east of Homs 28 Oct. More than 40 children reported killed in twin suicide bombings targeting primary school in regime-controlled Homs city 1 Oct.

U.S. late month began airstrikes against Islamic State (IS; formerly ISIL) militants and fighters linked to al-Qaeda (AQ) central leadership and AQ affiliate Jabhat al-Nusra (JN) inside Syria: dozens of IS fighters reported killed in Raqqah and Deir az-Zour provinces starting 23 Sept; Bahrain, Jordan, Qatar, Saudi Arabia, UAE participated in or provided support for operation. Scores reported killed in U.S. strikes targeting AQ-linked fighters in northern Aleppo and Idlib provinces; JN threatened retaliation. Observers expressed fears intervention risks strengthening IS, alienating other rebel groups; IS continued gaining ground, mid-month seized dozens of towns around predominantly Kurdish city Kobani near Turkish border; at least 160,000 Kurds fled, initially refused entry into Turkey sparking protests and clashes inside Turkey. Most of senior leadership of influential Ahrar as-Sham group among dozens killed in unexplained bomb blast in Idlib province 9 Sept; dead included group’s leader Hassan Aboud also acting as political chief of major rebel alliance Islamic Front; deaths seen as heavy blow to mainstream armed opposition. Regime mid-month revealed previously undeclared chemical facilities to Organisation for the Prohibition of Chemical Weapons (OPCW) confirming suspicions about earlier declarations, fuelling concerns toxic material could be seized by IS. Deadly regime airstrikes on rebel held areas continued including 25 reported killed in IS-held Raqqah city 6 Sept; at least 48 reported killed in Talbiseh north of Homs 16-17 Sept.

Situation continued to worsen for northern armed opposition: regime advance continued in Aleppo, jihadi Islamic State (IS; formerly ISIL or ISIS) gained north of city including capturing series of towns; Aleppo’s rebels expressed fears of impending defeat: regime pushing to encircle rebels inside city, IS fighting to recapture additional territory in northern countryside and push further west. Hostilities between regime and IS intensified: regime continued airstrikes on IS-held territory near Aleppo and further east, including dozens reported killed in Raqqah city mid-month; IS 8 Aug reportedly captured army base in Raqqah province, scores killed; hundreds reported killed, including in IS mass executions, after several days of fighting concluding in IS capture of Taqba air base, last regime stronghold in Raqqah province, 24 Aug. IS early to mid-month reportedly executed 700 members of al-Sheitat tribe in Deir al- Zour province in response to local uprising against IS rule. Tensions between al-Qaeda-linked Jabhat al-Nusra (JN) and former rebel allies continued in Idlib province; local JN chief reportedly assassinated 2 Aug. Regime and allied forces continued campaign around Damascus, scores reported killed in airstrikes: mid-month seized most of Mleiha town in eastern suburbs after months-long battle; area seen as strategic entry-point to eastern Ghouta, most significant remaining rebel stronghold in greater Damascus. U.S. late month reportedly started surveillance flights following military intervention against IS in Iraq (see Iraq)