Historians date the entry of Syrian regular troops to 1 June 1976 (Ménargues gives 9 June). President Assad announced it in the presence of the visiting Soviet Prime Minister Kosygin, citing appeals from the Akkar villages of Qubayat and Andaqit, besieged since January and attacked by the Lebanese Arab Army on 27 May. Columns moved towards Akkar and Tripoli, Zahleh and the Bekaa, and Sidon by way of Jezzine. Estimates of the force range from 6,000 men at the start (with 260 armoured vehicles, according to Ménargues) to 12,000-15,000 within weeks, with 250-300 tanks (de Clerck and Malsagne).

In Beirut in early June, Hanf writes, Fatah and its allies turned on Saiqa, the PLA and the pro-Syrian parties and cleared them from the city within a few hours. Syria's regular army stayed outside the capital for now: on 7 June its troops got as far as Sofar on the Beirut-Damascus road and into Sidon, where an armoured column was wiped out. Syrian forces reached Beirut only in mid-November, within the Arab Deterrent Force.

Picard (2016) dates to 9 June 1976 the Arab League Council resolution, taken in Cairo, that created an Arab peace force. Hanf has some 2,000 Sudanese arriving first, then Libyans; Picard (2002) says Tripoli sent 500 men in June.

Fisk reports that the bodies of Ambassador Francis Meloy, his economic counsellor Robert Waring and their Lebanese driver, abducted near the Museum crossing, were found that evening at Ramlet al-Baida, and that Arafat, once sure of the three Palestinians responsible, sent them to Tyre. De Clerck and Malsagne judge that the murders ended American efforts at a settlement through the Lebanese parties.

Barely a tenth of American and British residents accepted the evacuation, Fisk writes. The British went by road, the PLO escorting them through West Beirut and a Libyan officer on to the Syrian lines; a day later a US landing craft took evacuees off from a PLO-guarded bathing club on the Corniche.

Sudan supplied the Arab peace force's first contingent, some 2,000 men, and Libya the next (Hanf).

Yara El Khoury dates the start of the final offensive on Jisr al-Basha and Tal al-Za'tar to 22 June 1976, and Hanf's account (Jisr al-Basha stormed eight days after the first assault, on 1 July) points to the same week. The camps had been blockaded since January. Hanf says Chamoun's Tigers and Christian units of the army led the attack, the Kataeb joining later; a joint command of Bashir Gemayel (Kataeb), Dany Chamoun and Nabil Karam (NLP), Fawzi Mahfouz (Tanzim) and Etienne Saqr (Guardians of the Cedar) coordinated it (de Clerck and Malsagne).

Historians date the Ehden killings to 13 June (de Clerck and Malsagne) or 14 June (Hanf). A unit of some 200 men (Traboulsi) led by Samir Geagea attacked the Frangieh residence; besides Tony Frangieh, his wife and their three-year-old daughter, about thirty relatives and supporters were killed. The Phalange presented the raid as retaliation for the killing of their local leader Jud al-Bayeh in early June; Bashir Gemayel denied ordering the killing of the family. The raid also turned on control of the Chekka cement works. Syrian troops then occupied Ehden and much of the north.

Hanf writes that the Lebanese Front was left with an enclave of roughly a tenth of Lebanon once Syrian troops had moved into the northern Christian mountains, Koura, Batroun and the coast as far as the Madfoun bridge. Frangieh gave Kataeb members in the north until the month's end to give up their weapons and quit the party, or else leave.

The Qaa massacre is dated to the night of 27-28 June (de Clerck and Malsagne) or to 29 June (Hanf); Ras Baalbek and Jdeidet al-Fakiha were also raided. De Clerck and Malsagne blame Syrians in civilian clothes, carrying name lists and guided by local Christian members of the SSNP and the Communist Party, and see the killings as revenge for Ehden. Hanf counts 26 dead, de Clerck and Malsagne 32 to 36. The community's Supreme Council asked that a day of national mourning be held.

Bashir Gemayel's men fought a bloody battle with army units sent, at Pierre Gemayel's and Camille Chamoun's request, to separate the Kataeb and National Liberal militias, at war since 12 May. De Clerck and Malsagne call it the first serious armed clash between the army and a Lebanese militia, dating it once to 14 June and once to 18 June.

Ménargues dates the resignation to March 1980, after repeated deadlock between Hoss and Sarkis over the army; Hoss stayed on as caretaker until Shafiq Wazzan's appointment in late October.