Nearby localities include Talbiseh and al-Ghantu to the south, al-Zaafaraniyah and al-Mashrafah to the southeast, Murayj al-Durr to the northeast, Tumin to the north, Deir al-Fardis to the northwest and Kafr Nan and the Houla village cluster to the west.

Nonetheless, Arethusa became an independent city-state following Octavian's victory in the Battle of Actium in 31 BC, but returned to Emesani control eleven years later.

[19][20] In the time of Roman emperor Constantius II (337–361), Bishop Marcus (Mark) of Arethusa was authorized to replace a pagan temple in the city with a Christian church.

To avoid doing so he fled from the city, but returned to save the Christian people from paying the penalty in his stead, and in 362 underwent very cruel treatment at the hands of the pagan mob, as recounted by Theodoret and Sozomen.

Other bishops of Arethusa whose names are known are: a second Mark, who took part in the Council of Chalcedon in 451; Eusebius, one of the signatories of the letter that the bishops of Syria Secunda wrote to Emperor Leo I the Thracian after the killing of Patriarch Proterius of Alexandria; Severianus at the start of the 6th century; and Abraamius, who ordained the priest Constantinus of Apamea, accused of Monothelism at the Third Council of Constantinople (680–681).

[19][20] Lebanese sources such as Giuseppe Simone Assemani and Bishop Yusef al-Dibs claim that Maron, the patron saint of the Maronite Church, who died in 410, was buried in Arethusa.

[29] In early 945 the Aleppo-based Hamdanids under the leadership of Sayf al-Dawla decisively defeated the Ikhshidid army led by Abu al-Misk Kafur at ar-Rastan from which they proceeded to conquer Damascus.

[35] In a major battle at a place between the town and Homs, the Mamluks under Qalawun decisively defeated the invading Mongol army of the Ilkhanate in 1281.

[36] Later, in the early 14th century, Abu'l-Fida noted that in ar-Rastan, "Each of the houses is so large as to be almost like a village, with ruins everywhere round of buildings and walls."

[40] During the Franco-Syrian War, ar-Rastan served as one of the bases for Saleh al-Ali and his local allies and was shelled by French forces in early 1920.

The Hamdan had greater influence in the city and politically identified itself with the Nasserist trend which gained mass appeal in the Arab world in the 1950s–60s.

[42] On 23 March 1961, the Bulgarian Techno-Impex company completed the Rastan Dam while Syria was part of the United Arab Republic with Egypt.

[44] On 28 April about 50 local Ba'ath Party officials resigned from the organization in protest of the government and opposition activists claimed 17 demonstrators were killed by security forces.

That month saw the FSA target local government figures and sympathizers, and pro-government Shabiha militiamen attack opposition-held neighborhoods.

In late September the Syrian Army, reportedly backed by tanks and helicopters, launched an operation to retake the city resulting in four days of fighting.

[48] Opposition militants regained control of the city by January 2012 reigniting continuous clashes between them and the security forces which started late that month.

[50] On 6 February a local FSA unit commander Ala'a al-Sheikh reported that at least 42 people were killed by the Syrian Army in the preceding three days.

[53] In the northside of the city, the al-Bassel National Hospital is a major army base for government troops and is often the target of rebel shelling.