al-Muthanna ibn Haritha

Al-Muthanna ibn Haritha al-Shaybani (died 14 AH / 635 CE) was the Arab commander of the tribes of lower Iraq who played a decisive role in the opening phase of the Islamic conquest of Persia. Before the main Muslim armies arrived, al-Muthanna ibn Haritha had been leading raids into the Sassanid-controlled borderlands with the tribes under his command, motivated both by plunder and by the strategic vacuum left by the exhausted Persian empire.

He traveled to Medina and presented himself to Abu Bakr al-Siddiq after the Prophet's death, requesting authorization and support for formal raids into Persia. Abu Bakr granted his request and assigned him Khalid ibn al-Walid as overall commander. Together they fought the early battles of the Iraq campaign, with al-Muthanna providing crucial local knowledge, tribal support, and manpower.

After Khalid was transferred to Syria, al-Muthanna became the main Muslim commander in Iraq. He suffered a serious defeat at the Battle of the Bridge (Jisr) in 13 AH against Sassanid forces, losing a significant portion of his army. He rallied, requested reinforcements, and continued fighting. His persistent pressure on the Persians helped maintain the Muslim foothold in lower Iraq until Sa'd ibn Abi Waqqas arrived with the main army.

Al-Muthanna was wounded at the Battle of Buwayb and died from his wounds around 14 AH before the decisive Battle of al-Qadisiyyah, which fulfilled the strategic goals he had worked toward. He left behind a request that Sa'd ibn Abi Waqqas marry his widow Salma, which Sa'd did — symbolizing the continuity of the conquest he had begun.