Battle of River

Part of Islamic conquest of Persia and
Campaigns of Khalid ibn al-Walid

Date	April 633
Location	Mesopotamia (Iraq)
Result	Decisive Rashidun Caliphate victory

Belligerents

Rashidun Caliphate

Sasanian Empire,
Arab allies

Commanders and leaders

Khalid ibn al-Walid

Qarin †,
Qubad †,
Anoshagan †

Strength

~17,000

30.000-50.000

Casualties and losses

Unknown

30,000(primary sources)
10,000-15,000

According to Arab and Muslim sources, the Battle of River took place in Mesopotamia (Iraq) between the forces of the Rashidun Caliphate and the Sasanian Empire. Muslims, under Khalid ibn al-Walid's command, defeated the numerically superior Persian army.

The Prophet Mohammad died on 8 June 632, and Abu Bakr succeeded him as first Caliph. Abu Bakr's Caliphate lasted for 27 months, during which he crushed the rebellion of the Arab tribes throughout Arabia in the successful campaign against apostasy and restore the authority of Madinah over Arabia. Once the rebellions had been put down, Abu Bakr began a war of conquest. He launched campaigns against the Sassanid Empire and the Eastern Roman Empire (Byzantine Empire) and thus set in motion a historical trajectory that in just a few short decades would lead to one of the largest empires in history.

After the Ridda Wars, a Muslim tribal chief raided the Persian frontier towns in Iraq. After the success of these raids Abu Bakr planned to expand his empire. He started with Iraq, a rich Persian province. After centuries of Persian power and glory, it was important for Abu Bakr's expedition to not to suffer a defeat, for that would confirm and strengthen the fear for the Persian military strength. To overcome these concerns he decided that the army that would invade Persia would consist entirely of volunteers. He put in command of the army his best general Khalid ibn al-Walid. Muslims invaded the Sassanid Persian Empire in April 633 and defeated the Sassanid army in the Battle of Chains, where the Marzbān (provincial governor) Hormuz was killed by Khalid ibn al-Walid in a duel.

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Wikipedia