During the 1960s Lebanon was relatively calm, but this would soon change. Fatah and other Palestinian Liberation Organization factions had long been active among the 400,000 Palestinian refugees in Lebanese camps. Throughout the 1960s, the center for armed Palestinian activities had been in Jordan, but they were forced to relocate after being evicted by King Hussein during the Black September in Jordan. Fatah and other Palestinians groups had attempted to mount a coup in Jordan by incentivizing a split in the Jordanian army, something that the ANM had attempted to do a decade earlier by Nasser's bidding. Jordan, however, responded and expelled the forces into Lebanon. When they arrived they created "a State within the State". This action wasn't welcomed by the Lebanese government and this shook Lebanon's fragile sectarian climate.
Solidarity to the Palestinians was expressed through the Lebanese Sunni Muslims but with the aim to change the political system from one of consensus amongst different sects, towards one where their power share would increase. Certain groups in the Lebanese National Movement wished to bring about a more secular and democratic order, but as this group increasingly included Islamist groups, encouraged to join by the PLO, the more progressive demands of the initial agenda was dropped by January 1976. Islamists did not support a secular order in Lebanon and wished to bring about rule by Muslim clerics. Yezid Sayigh documents these events, especially the role of Fatah and the Tripoli Islamist movement known as Tawhid, in changing the agenda being pursued by many groups, including Communists. This ragtag coalition has often been referred to as left-wing, but many participants were actually very conservative religious elements that did not share any broader ideological agenda; rather, they were brought together by the short-term goal of overthrowing the established political order, each motivated by their own grievances.