[5][2] The origins of the Lions of the East Army trace back to the rebellion in Deir ez-Zor Governorate from 2011 to 2014, when several rebel groups emerged to fight against Bashar al-Assad's government.

[2][1] Salama eventually became one of the most prominent anti-ISIL rebel leaders in the governorate,[2] while his group became known for helping government officers and soldiers in Deir ez-Zor to defect by smuggling them to their home areas.

[1] There, Liwa Bashair al-Nasr merged with eleven other ex-Deir ez-Zor factions,[2] forming the "Lions of the East Army" under Salama's leadership.

Eventually, Liwa Usud al-’Asima left the Lions of the East Army and merged with Jaysh al-Islam's 8th Brigade.

[2] Since its formation, the Lions of the East Army has fought alongside other rebel groups against ISIL in the southern Syrian Desert and the Qalamoun Mountains, and despite reversals has managed to capture much territory.

[1] In April 2018, along with other rebel groups in the eastern Qalamoun, fighters of the Lions of the East Army were evacuated to Turkish-occupied areas in the northern Aleppo Governorate, thus leaving the Southern Front coalition.

Although the army came into existence as a merger of 12 rebel factions, with more units such as the Lions of Sunna Brigade joining later, these groups have fully integrated into the organization and abandoned their individual identities.

Lions of the East fighters are trained and paid a salary of $150 per month by the Military Operations Center (MOC) based in Amman, Jordan.