Battle of the Yarmuk

Battle of the Yarmuk (also spelled Yarmouk) was a major battle fought between the Byzantine Empire and the Arab Muslim forces of the Rashidun Caliphate. The battle, consisting of a series of engagements over six days, took place from August 15 to August 20, 636, near the Yarmuk River (also called the Hieromyces River) along the present-day borders of Syria–Jordan and Syria-Israel, southeast of the Sea of Galilee. The result was a decisive victory for the Rashidun Caliphate, leading to the end of Roman rule in Syria after about seven centuries.

Battle of the Yarmuk
Part of Muslim conquest of the Levant
Date 15–20 August 636 Location Near the Yarmuk River, Syria Result Rashidun Caliphate victory
Strength
15,000–40,000 (modern estimates) 24,000–40,000 (primary Arab sources)	40,000–100,000 (modern estimates) 100,000–200,000 (primary Arab sources) 140,000 (primary Roman sources)
Casualties and losses
4,000 killed	40,000 (modern estimates) 70,000–120,000 killed (primary Arab sources)

Background

During the Byzantine–Sasanian War of 602–628, Heraclius became the Byzantine Emperor in 610. After expelling the Persians from Anatolia and achieving victories, he managed to restore the True Cross to Jerusalem in 629. Concurrently, the rise of Islam under Muhammad led to the unification of the Arabian Peninsula.

After Muhammad's death in 632, his successor Abu Bakr launched a series of conquests, including the invasion of Syria. The Rashidun forces, led by Khalid ibn al-Walid, achieved significant victories against the Byzantine forces, including at the Battle of Ajnadayn and the capture of Damascus in 635.

Byzantine Counterattack

In response to the Muslim conquests, Byzantine Emperor Heraclius prepared a large counteroffensive. By May 636, he had assembled a vast army from various regions. Despite this, coordination with an allied Persian counteroffensive failed. The Byzantine forces, commanded by Theodore Trithyrius, Vahan, Buccinator, Jabalah ibn al-Aiham, and others, advanced towards the Yarmuk River.

The Battle

The battle took place in the Yarmuk River basin. The Rashidun forces, commanded by Khalid ibn al-Walid, Abu Ubayda ibn al-Jarrah, and other leaders, used tactical withdrawals and reinforcements to overcome the larger Byzantine army. The victory at Yarmuk marked the end of Byzantine control in Syria and led to the rapid expansion of the Rashidun Caliphate into the Levant.

Aftermath

The Battle of Yarmuk had significant repercussions, leading to the annexation of the Levant by the Rashidun Caliphate and weakening Byzantine influence in the region. The battle is considered one of the most decisive in military history.