Syrian occupation of Lebanon The Syrian occupation of Lebanon began in 1976 as a result of the civil war and ended in April 2005 in response to domestic and international pressure after the assassination of former Lebanese Prime Minister , Rafik Hariri . In January 1976 , a Syrian proposal to restore the limits to the Palestinian guerrilla presence in Lebanon , which had been in place prior to the outbreak of the civil war , was welcomed by Maronites and conservative Muslims , but rejected by the Palestinian guerrillas and their Lebanese Druze - led and leftist allies . In June 1976 , to deal with the opposition posed by this latter group ( which was normally allied with Syria ) , Syria dispatched Palestinian units under its control into Lebanon , and soon after sent in its own troops as well . Syrian claims these interventions came in response to appeals from Christian villagers under attack by Leftists in Lebanon . By October 1976 , Syria had caused significant damage to the strength of the Leftists and their Palestinian allies , but at a meeting of the Arab League , it was forced to accept a ceasefire . The League ministers decided to expand an existing small Arab peacekeeping force in Lebanon , but it grew to be a large Arab Deterrent Force consisting almost entirely of Syrian troops . The Syrian military intervention was thus legitimized and received subsidies from the Arab League for its activities . Analyzing whether and when the Syrian presence was a military occupation under international law , Gerhard von Glahn claimed that the mandate of the Force was renewed several times before it officially expired on July 27 , 1982 . The Lebanese government refused to request that the mandate be renewed by the Arab League and instead , in September 1986 , Lebanon actually requested an end to the Syrian presence in Lebanon . Hence , according to von Glahn , it appeared that lacking legal authority from both Lebanon and the Arab League , Syria ' s military forces had to be regarded henceforth as illegal occupants of Lebanon . " In 1989 , at the final accords of the civil war , two rival administrations were formed in Lebanon : a military one under Aoun in East Beirut and a civilian one under Selim el - Hoss based in West Beirut ; the latter gained the support of the Syrians . Aoun opposed the Syrian presence in Lebanon , citing the 1982 UN Security Council Resolution 520 . In the resulting " War of Liberation " , which erupted in March 1989 , Aoun ' s forces were defeated and he himself exiled from Lebanon . In 1991 , a Treaty of " Brotherhood , Cooperation , and Coordination " , signed between Lebanon and Syria , legitimized the Syrian military presence in Lebanon . It stipulated that Lebanon would not be made a threat to Syria ' s security and that Syria was responsible for protecting Lebanon from external threats . In September that same year a Defense and Security Pact was enacted between the two countries . Following the assassination of the Lebanese ex - premier Rafik Hariri in 2005 , and an alleged involvement of Syria in his death , a public uprising nicknamed Cedar Revolution had swept the country . With the consequent adoption of UN resolution 1559 , Syria was forced to announce its full withdrawal from Lebanon on April 30 , 2005 . Background . The Lebanese civil war that began on April 13 , 1975 was the backdrop against which the Syrian military presence in Lebanon was established . In January 1976 , its proposal to restore the limits to the Palestinian guerrilla presence in Lebanon , that had been in place prior to the outbreak of the civil war , was welcomed by Maronite s and conservative Muslims , but rejected by the Palestinian guerrillas and their Lebanese Druze - led and leftist allies . Syria ' s interventions came in response to appeals from Maronite leaders , who feared attack by leftists and Palestinians . In a 1976 diplomatic cable released by Wikileaks , a US diplomat stated " if I got nothing else from my meeting with Frangie , Chamoun and Gemayel , it is their clear , unequivocal and unmistakable belief that their principle hope for saving Christian necks is Syria . They sound like Assad is the latest incarnation of the Crusaders . " Occupation period . By October 1976 , Syria had caused significant damage to the strength of the leftists and their Palestinian allies , but at a meeting of the Arab League , it was forced to accept a ceasefire . The League ministers decided to expand an existing small Arab peacekeeping force in Lebanon . It grew to be a large deterrent force consisting almost entirely of Syrian troops . The Syrian military intervention was thus legitimized and received subsidies from the Arab League for its activities . In the late 1980s , General Michel Aoun was appointed President of the Council of Ministers by President Amine Gemayel , a controversial move since Aoun was a Maronite Christian and the post was by unwritten convention reserved for a Sunni Muslim . Muslim ministers refused to serve in Aoun ' s government , which was not recognized by Syria . Two rival administrations were formed : a military one under Aoun in East Beirut and a civilian one under Selim el - Hoss based in West Beirut ; the latter gained the support of the Syrians . Aoun opposed the Syrian presence in Lebanon , citing the 1982 UN Security Council Resolution 520 . The Syrian military remained in Lebanon ; after a successful campaign against the Lebanese Forces militia who had controlled Beirut port , Aoun , now with massive popular support in his East Beirut enclave , declared a " War of Liberation " against the Syrian forces . Fighting began on 14 March 1989 . Casualties among civilians on both sides from indiscriminate artillery bombardments across the front line were numerous . Aoun initially received a greater degree of international support than el - Hoss , but this ended abruptly with the American build - up for war with Iraq over Kuwait . Aoun had received considerable support from the Iraqi government , anxious to weaken the rival Baathist government in Damascus ; in October 1990 Syrian forces took the presidential palace at Baabda . Aoun took refuge in the French embassy and was later exiled from Lebanon to France . Circumstances surrounding his exile are controversial ; his apprehension and exile are variously attributed to Syrian forces , Israeli Defense Force s , Shiite militias , and the Lebanese Forces militia of Samir Geagea . Since then , Syrian forces remained in Lebanon , exercising considerable influence . In 1991 , a Treaty of " Brotherhood , Cooperation , and Coordination " , signed between Lebanon and Syria , legitimized the Syrian military presence in Lebanon . It stipulated that Lebanon would not be made a threat to Syria ' s security and that Syria was responsible for protecting Lebanon from external threats . In September that same year a Defense and Security Pact was enacted between the two countries . After the Israeli withdrawal from southern Lebanon and the death of Hafez Al - Assad in 2000 , the Syrian military presence faced criticism and resistance from the Lebanese population . Following the assassination of the Lebanese ex - premier Rafik Hariri , and an alleged involvement of Syria in his death a public uprising nicknamed Cedar Revolution had swept the country . With the consequent adoption of UN resolution 1559 , Syria was forced to announce its full withdrawal from Lebanon on April 30 , 2005 . Units involved . Between 1976 and 2005 , Syria had on average between 20 , 000 and 40 , 000 troops in Lebanon . The major formations deployed in Lebanon were the 47th Armoured Brigade , 62nd Armoured Brigade , most of the 10th Mechanized Division ( 2 Armoured Brigades - the 76th and the 91st , 1 Mechanized Infantry Brigade , 1 Artillery Brigade ) , plus 5 Special Forces regiments deployed in strategic and tactical locations , and at least 1 Air Defense Brigade . Before 1984 , a brigade of the Defense Companies was also deployed in Beirut , Sidon and Tripoli to fight Sunni militias and train pro - Syrian militias . Officers of the Military Intelligence , General Security Directorate and Air Force intelligence were tasked with Syria ' s administration in Lebanon . Ghazi Kanaan and Rustum Ghazaleh were the two intelligence officers who controlled Lebanon throughout this period . Diplomatic exchange . In October 2008 , both Syria and Lebanon decided to have diplomatic relationships by establishing embassies for the first time in history since both countries gained their national independence during the 1940s . Two months later , the Syrian Embassy was opened in Beirut . In March 2009 , Lebanon followed and opened its embassy in Damascus . Special Tribunal for Lebanon . The Special Tribunal for Lebanon was formed in the wake of the assassination of former Prime Minister Rafik Hariri on 14 February 2005 . Following which the Syrian military presence ended on 26 April 2005 after the Cedar Revolution that took place as a reaction to the assassination . In 2010 , as rumours abounded of an indictment to members of Hezbollah and rising tensions , Syrian President Bashar al - Assad visited Lebanon for the first time since the Hariri ' s assassination along with Saudi King Abdullah . Political status . Analyzing whether and when the Syrian presence was a military occupation under international law , Gerhard von Glahn writes that " The mandate of the Force was renewed several times before it officially expired on July 27 , 1982 , at the time of the Israeli siege of Beirut . The Lebanese government refused to request that the mandate be renewed by the Arab League . Instead , in September 1986 , Lebanon requested an end to the Syrian presence in Lebanon . It would appear that , lacking legal authority from both Lebanon and the Arab League , Syria ' s military forces had to be regarded henceforth as illegal occupants of Lebanon . "