Counts of those evacuated between 21 August and 1 September differ: 14,398 Palestinians and Syrians, including 664 women and children of PLO cadres (de Clerck and Malsagne); 14,938 Palestinians by 30 August (Ménargues); about 15,000 by sea plus 6,500 Syrian and PLA soldiers by land (Hanf). On 1 September President Reagan announced his peace plan.

Figures differ by source and cut-off date. De Clerck and Malsagne cite a Lebanese police report of November 1982 covering 4 June to 21 August: 19,085 dead, 6,775 of them in Beirut and 84% of them civilians, and 30,302 wounded. Ménargues, citing police reports, gives 17,825 dead and 30,103 wounded from 4 June; Fisk gives almost 17,825 dead from 4 June to the end of September. Picard cites UNICEF: 29,506 dead and wounded between 4 June and 15 August, 80% of them civilians in Beirut and its suburbs. The 6,775 dead in the original therefore appear to be Beirut's share only.

The Marines pulled out on 10 September, a week or more before their mandate expired; the Italians left on 11 September and the French on 12–13 September (Ménargues, Hanf). Their last landing craft bore a 'Mission accomplished' banner. The Sabra and Chatila massacre began a few days after the last French troops left.

Bashir Gemayel was killed at about 4 p.m. during his weekly visit to the Kataeb office in Ashrafieh, nine days before taking office. The bomb, about 35 kilos of explosive, had been placed two days earlier in the flat above by Habib Tanios Chartouni, a member of the Syrian Social Nationalist Party, arrested on 16 September (Ménargues). Prime Minister Wazzan announced the death at midnight. Hanf counts 26 dead.

In Ménargues's account of the Bikfaya funeral, Bashir's coffin was carried from the church of Mar Abda onto a gun carriage before the entire government, the diplomatic corps and every deputy, even those who had boycotted his election. Israeli troops had entered West Beirut at 5 a.m. that day, breaching the agreement negotiated by Philip Habib.

Israeli troops entered West Beirut at 5 a.m. on 15 September, the morning after Bashir Gemayel's death, against the commitments given through Philip Habib; Lebanese leftist militias fought them in parts of the city.

Jawad Boulos was one of three 'wise men' in the leadership of the Christian Lebanese Front, with Fouad Ephrem Boustani and Charles Malek (Hanf).

The massacre lasted from the evening of Thursday 16 September to the morning of Saturday 18 September (Traboulsi gives 15-17, Hanf 17-18). The killers were militiamen of the Lebanese Forces' security service under Elie Hobeika, together with men of Saad Haddad's South Lebanon militia. The Israeli army, which controlled the area after entering West Beirut on 15 September, let them into the camps, lit the camps with flares at night and watched from command posts nearby. Israel's Kahan Commission, published on 7 February 1983, held the Phalangists directly responsible and found Defence Minister Ariel Sharon personally responsible, recommending his removal; it also attributed indirect responsibility to other Israeli political and military leaders. Estimates of the dead range from about 460-800 to 3,500; Bayan Nuwayhed al-Hout's survey found victims of twelve nationalities, about half Palestinian and more than a quarter Lebanese.

Amine Gemayel was elected in the same Fayadiyeh barracks as his brother, with 77 votes of the 80 deputies present (Hanf). On the evening of 20 September Israeli ministers Yitzhak Shamir and Ariel Sharon had met him secretly at Dbayeh (Ménargues).

On 8 November 1982 PSP men attacked a Christian funeral in Kfar Nabrakh, a mixed Chouf village, killing eleven, in reaction to a Lebanese Forces checkpoint set up nearby. Some twenty houses were burned and nine villagers abducted; their bodies were found in a well on 23 November. De Clerck and Malsagne call it the Mountain War's first massacre.