# Battle of Yarmouk (15–20 August 636)

URL: https://allhistories.com/jordan/timeline/636-battle-of-yarmouk
Location: Yarmouk River, Jordan–Syria border
Themes: main-event

From 15 to 20 August 636 the Rashidun army and Byzantine field forces fought for six days on a plain east of Wadi ur-Ruqqad near the Yarmouk River, on what is now the Syria–Jordan border. Decisive fighting took place on 20 August; some accounts describe a one-day battle. Khalid ibn al-Walid led the Muslim army after taking command from Abu Ubayda, and his mobile cavalry was decisive. The Byzantine commanders were the Armenian Vahan and Theodore Trithyrius, who was killed. Early Arab sources give Byzantine numbers of 100,000–200,000, modern estimates 15,000–50,000, and Treadgold 80,000–100,000 or more; Muslim strength is usually put at 15,000–40,000. Arab sources report about 5,000 Muslim dead and tens of thousands of Byzantine dead. It was a decisive Arab victory that effectively ended Byzantine rule in Syria and opened Palestine, Transjordan and the north to conquest. The emperor withdrew from Syria, and Amr ibn al-As later captured Egypt in 639–642. At this point in the timeline (636), Umar (636 – 644) reigned as Caliph; the territory lay within the province of Jund al-Urdunn within Bilad al-Sham.

## Why it matters
The battle effectively decided the fate of Syria and Transjordan and is often cited as one of the most decisive battles in military history.

Ruler at the Time: [Umar](https://allhistories.com/jordan/rulers/umar-636)

## Sources
- [Wikipedia — Battle of Yarmouk](https://en.wikipedia.org/wiki/Battle_of_Yarmouk)
- [Wikipedia — Muslim conquest of the Levant](https://en.wikipedia.org/wiki/Muslim_conquest_of_the_Levant)
- [Wikipedia — Ghassanids](https://en.wikipedia.org/wiki/Ghassanids)