Battle of Ullais

Overview of the region where the Battle of Ullais was fought, showing the river Euphrates and its tributary the Khaseef (Iraq).

Date	May 633 A.D
Location	Iraq
Result	Decisive Rashidun Caliphate Victory.

Belligerents

Rashidun Caliphate

Sassanid Persian Empire
Arab allies.

Commanders and leaders

Khalid ibn al-Walid

Jaban
Abdul-Aswad†
Abjar†.

Strength

15,000

70,000
(primary sources)
30,000 - 35,000
(modern estimates)

Casualties and losses

~2,000

Entire army

The Battle of Ullais was fought between the forces of the Rashidun Caliphate and the Sassanid Persian Empire in the middle of May 633 AD in Iraq, and is sometimes referred to as the Battle of Blood River since, as a result of the battle, there were enormous amounts of Sassanian and Arab Christian casualties.

Before taking on the Persians Khalid ibn al-Walid wrote to Hormuz, the Persian governor of the frontier district of Dast Meisan, saying:

This was now the last of four consecutive battles that were fought between invading Muslims and the Persian army. After each battle the Persians and their allies regrouped and fought again. These battles resulted in the retreat of the Sassanid Persian army from Iraq and its capture by Muslims under the Rashidun Caliphate.

After defeat at the Battle of Walaja, Christian Arab survivors of the battle fled from the battlefield, crossed the River Khaseef (a tributary of the Euphrates) and moved between it and the Euphrates. Their flight ended at Ullais, about 10 miles from the location of the Battle of Walaja. The Muslims were aware of the presence of hostile Arabs at Ullais but, as they were less numerous and were survivors of Walaja, they never considered them a military threat until they started to regroup and the Muslim commander Khalid ibn Walid was informed about the arrival of more Arab hordes, mainly from the Christian Arab tribe of Bani Bakr. More reinforcements were raised from the Christian Arab tribes in the region between Al-Hirah and Ullais. The Rashidun Caliphate army under Khalid crossed the river Khaseef and approached Ullais frontally. Emperor Ardsheer meanwhile sent orders to Bahman Jaduya to proceed to Ullais and take command of Arab contingents there and stop the Muslims advance at Ullais. Bahman sent his senior general Jaban with the imperial army to Ullais with orders to avoid battle until Bahman Jaduya himself arrived. As Jaban set off with the army, Bahman Jaduya returned to Ctesiphon to discuss certain matters with the Emperor. He arrived at Ctesiphon to find Emperor Ardsheer very ill and remained in attendance on him. By now the Persians and Arabs had realised that the Muslims' objective was Al-Hirah. They decided to fight and defeat the Muslims army. The Christian Arab contingents were under the command of a tribal chief called Abdul-Aswad, who had lost his two sons in the Battle of Walaja against the Muslims and wanted revenge.

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Wikipedia