Most sources put the start of the war at 27 May, while the British consul considered 29 May the actual start of full-fledged conflict.
The first major outbreak of violence occurred when a 250-strong Maronite militia from Keserwan led by Taniyus Shahin went to collect the silk harvest from Naccache, but instead of returning to Keserwan, proceeded to Baabda in the al-Sahil district near Beirut.
The local Druze leadership considered the Maronite mobilization at Baabda to be a provocation to the Druze in the mixed Metn district, while the Maronites saw the garrisoning of Ottoman troops under Khurshid Pasha near Naccache on 26 May as a prelude to a Druze assault.
The Ottoman garrison established itself at Hazmiyeh with the support of the European consuls in order to bring order to Mount Lebanon.
However, the Maronites considered it a threat since they viewed the Ottomans as allies of the Druze.

On 29 May, Keserwani Maronites raided the mixed villages of Qarnayel, Btekhnay and Salima and forced out its Druze residents.
The tension broke out into open conflict later that day during a Druze assault against the mixed village of Beit Mery, with the village's Druze and Christian residents subsequently calling for support from their co-religionists in Abadiyeh and al-Sahil, respectively.
The Druze, backed by an Ottoman commander of irregulars named Ibrahim Agha, and Maronite fighters burned down the houses of the rival sect in Beit Mery.
The Maronite fighters defeated the Druze and Ibrahim Agha at Beit Mery before withdrawing from the village.

On 30 May, the Keserwani Maronite militiamen attempted to renew their assault against Beit Mery, but were countered by 1,800-2,000 Druze militiamen led by the Talhuq and Abu Nakad clans on the way, prompting previously neutral Maronites from Baabda, Wadi Shahrur, Hadath and elsewhere in al-Sahil to join the fighting.
Although casualties among the Christian militiamen were relatively low during the fighting on 30 May, in the renewed battle on 31 May, the 200-strong Maronite force was routed at Beit Mery and forced to retreat to Brummana.
By the day's end, the Druze fighters were in complete control of Metn, where clashes were widespread, and between 35 and 40 Maronite majority villages were set alight and some 600 Maronites in the district slain.

Also on 30 May, full-fledged fighting between Druze and Christians occurred in the area of Zahle, when a 200-strong Druze force led by Ali ibn Khattar Imad confronted 400 local Christian fighters at the village of Dahr al-Baidar, prompting Christian militiamen from nearby Zahle to join the fighting.
Imad's men retreated to Ain Dara, where the Christians followed them before being defeated.
Ali Imad died of his wounds on 3 June; consequently, a 600-strong Druze force was mobilized under the command of his father Khattar Imad.
Some 3,000 Christian fighters, predominantly from Zahle, met Khattar's forces near Ain Dara where a major battle took place.
The Druze experienced twice as many casualties as the Christians, but ultimately forced the Christians to retreat to Zahle.
Between 29 and 31 May, 60 villages were destroyed in the vicinity of Beirut, and 33 Christians and 48 Druzes were killed.

In the last days of May, Druze forces under the command of Bashir Nakad and backed by the Imad and Jumblatt clans besieged Deir al-Qamar.
In the first days of June, reports from the town to European consuls reported that starvation was beginning to set in.
A relief supply of grain and flour sent by the Ottoman general Khurshid Pasha apparently did not reach the town.
Bashir's forces, numbering some 3,000 Druze fighters, launched an assault on Deir al-Qamar on 2 June and another assault the next day.
The Christian defenders in Deir al-Qamar initially put up stiff resistance and inflicted heavy casualties on the Druze forces, who managed to raze the town's outskirts.
After eight hours of the Druze assault, Deir al-Qamar surrendered on 3 June, partially as a result of internal divisions among the town's Christian militia.
Fatality reports ranged from 70 to 100 slain Druz
Most sources put the start of the war at 27 May, while the British consul considered 29 May the actual start of full-fledged conflict. The first major outbreak of violence occurred when a 250-strong Maronite militia from Keserwan led by Taniyus Shahin went to collect the silk harvest from Naccache, but instead of returning to Keserwan, proceeded to Baabda in the al-Sahil district near Beirut. The local Druze leadership considered the Maronite mobilization at Baabda to be a provocation to the Druze in the mixed Metn district, while the Maronites saw the garrisoning of Ottoman troops under Khurshid Pasha near Naccache on 26 May as a prelude to a Druze assault. The Ottoman garrison established itself at Hazmiyeh with the support of the European consuls in order to bring order to Mount Lebanon. However, the Maronites considered it a threat since they viewed the Ottomans as allies of the Druze.
On 29 May, Keserwani Maronites raided the mixed villages of Qarnayel, Btekhnay and Salima and forced out its Druze residents. The tension broke out into open conflict later that day during a Druze assault against the mixed village of Beit Mery, with the village's Druze and Christian residents subsequently calling for support from their co-religionists in Abadiyeh and al-Sahil, respectively. The Druze, backed by an Ottoman commander of irregulars named Ibrahim Agha, and Maronite fighters burned down the houses of the rival sect in Beit Mery. The Maronite fighters defeated the Druze and Ibrahim Agha at Beit Mery before withdrawing from the village.
On 30 May, the Keserwani Maronite militiamen attempted to renew their assault against Beit Mery, but were countered by 1,800-2,000 Druze militiamen led by the Talhuq and Abu Nakad clans on the way, prompting previously neutral Maronites from Baabda, Wadi Shahrur, Hadath and elsewhere in al-Sahil to join the fighting. Although casualties among the Christian militiamen were relatively low during the fighting on 30 May, in the renewed battle on 31 May, the 200-strong Maronite force was routed at Beit Mery and forced to retreat to Brummana. By the day's end, the Druze fighters were in complete control of Metn, where clashes were widespread, and between 35 and 40 Maronite majority villages were set alight and some 600 Maronites in the district slain.
Also on 30 May, full-fledged fighting between Druze and Christians occurred in the area of Zahle, when a 200-strong Druze force led by Ali ibn Khattar Imad confronted 400 local Christian fighters at the village of Dahr al-Baidar, prompting Christian militiamen from nearby Zahle to join the fighting. Imad's men retreated to Ain Dara, where the Christians followed them before being defeated. Ali Imad died of his wounds on 3 June; consequently, a 600-strong Druze force was mobilized under the command of his father Khattar Imad. Some 3,000 Christian fighters, predominantly from Zahle, met Khattar's forces near Ain Dara where a major battle took place. The Druze experienced twice as many casualties as the Christians, but ultimately forced the Christians to retreat to Zahle. Between 29 and 31 May, 60 villages were destroyed in the vicinity of Beirut, and 33 Christians and 48 Druzes were killed.
In the last days of May, Druze forces under the command of Bashir Nakad and backed by the Imad and Jumblatt clans besieged Deir al-Qamar. In the first days of June, reports from the town to European consuls reported that starvation was beginning to set in. A relief supply of grain and flour sent by the Ottoman general Khurshid Pasha apparently did not reach the town. Bashir's forces, numbering some 3,000 Druze fighters, launched an assault on Deir al-Qamar on 2 June and another assault the next day. The Christian defenders in Deir al-Qamar initially put up stiff resistance and inflicted heavy casualties on the Druze forces, who managed to raze the town's outskirts. After eight hours of the Druze assault, Deir al-Qamar surrendered on 3 June, partially as a result of internal divisions among the town's Christian militia. Fatality reports ranged from 70 to 100 slain Druz
1860 Mount Lebanon civil war