The IUM was founded in Tripoli in 1982 a splinter faction of the Lebanese Islamic Group[1] led by Sheikh Said Shaaban, one of Lebanon’s Islamist movements’ few charismatic Sunni religious leaders.

Consistent with these principles, Shaaban and its Movement ostensibly rejected Nationalism, sectarianism and democratic pluralism in favor of an Islamic rule that "absorbs and dissolves all social differences and unites them in one crucible".

As such, the IUM strongly opposed the Christian-dominated political order in Lebanon and deeply resented the Syrian military intervention of June 1976 in support of the Maronites who, Shaaban himself asserted, would have otherwise fled to Cyprus or Latin America.

[10] Controlled by the IUM's Military Command Council (Arabic: Majliss al-Kiyadi al-Harb) headed by Sheikh Hashem Minqara, their 1,000-men strong militia, also designated 'Tawheed', was created in 1982 and trained by the Palestine Liberation Organization (PLO), being initially provided with light weapons drawn from Lebanese Armed Forces (LAF) and Internal Security Forces (ISF) stocks or purchased on the black market.

Upon the withdrawal of the Palestinian factions loyal to Yasser Arafat from Tripoli in December 1983, the Tawheed seized the opportunity to replenish themselves with vehicles, additional weapons and ammunition from PLO arms caches left behind.

The IUM militia was also able to raise a mechanized force made of ex-PLO Gun trucks and technicals, comprising Spanish Santana 88 Ligero Militar jeeps,[15] Land-Rover series II-III, Chevrolet C-10/C-15 Cheyenne,[16] Toyota Land Cruiser (J40/J42), Toyota Land Cruiser (J75) and Datsun 620 light pickups, and Mercedes-Benz Unimog 404 and 416 light trucks[17] armed with heavy machine guns, recoilless rifles and anti-aircraft autocannons.

[20] The IUM has its main strongholds at the predominantly Sunni district of Bab al-Tabbaneh in the western part of Tripoli, where the group's headquarters is located, and the Dinniyeh sub-urban area east of the city.

They also controlled the nearby clandestine port of al-Mahdi, set up at Tripoli's western outskirts at El Mina and run by the Sunni businessmen Tariq Fakhr al-Din, which was employed mainly for arms-smuggling operations and to levy illegal taxes on the transit trade of agricultural products and other goods.

In one occasion, Tawheed fighters rounded up some 52 top Communist members, forced them to renounce their atheism and then summarily shot them, dumping the victims' bodies into the Mediterranean.

The reference to "El-Tawhid" may have been confused with the group Abu Mussab al-Zarqawi lead, Al Qaeda in Iraq, used to be called "Jama'at al-Tawhid wal-Jihad".

Aided by a coalition of ADP, SSNP, Lebanese Communist Party/Popular Guard, and Baath Party militias, the Syrians managed to defeat decisively the Tawheed in another round of brutal fighting on the streets of Tripoli, killing many of its fighters, arresting others and scattered the remainder.

From 1988 to 2000, the Movement's guerrillas at the Jabal Amel fought alongside the Shia Hezbollah against the Israel Defense Forces (IDF) and their South Lebanese Army (SLA) proxies in the Israeli-controlled "Security Belt".