Siege of Ctesiphon ( 637 ) The successful Siege of Ctesiphon ( , also known as ' Al - Mada ' in المدائن in Arabic ) by the Rashidun army lasted about two months , from January to March 637 . Ctesiphon , located on the east bank of the Tigris , was one of the great cities of the Persian Empire , an imperial capital of the Arsacid s and of their successors , the Sassanids . Soon after the conquest of the city by Muslims , Sassanid rule in Iraq ended . Ctesiphon is located approximately at Al - Mada ' in , 20 miles southeast of the modern city of Baghdad , Iraq , along the river Tigris . Ctesiphon measured 30 square kilometers . The only visible remnant is the great arch Taq - i Kisra located in what is now the Iraqi town of Salman Pak . March to Ctesiphon . After the decisive victory at Battle of Qadisiyyah , Caliph Umar decided to capture the Sassanid Persian capital city of Ctesiphon , because as long as the Sassanids held their capital at Ctesiphon , there was always a possibility that sooner or later they could mount another counter - attack . Umar accordingly ordered Saad , the Muslim commander in chief in Iraq , to march against Ctesiphon . In December 636 , Saad marched with a Muslim army of 15 , 000 towards Ctesiphon . The Sassanian Emperor Yazdgerd III feared that Muslims would next march against Ctesiphon . As he received the intelligence of preparation of Muslims ' march against Ctesiphon he deployed detachments of whatever troops he had at capital on the main stages to the route to Ctesiphon , so that necessary arrangement could be done for the defense of the capital city . Meanwhile he hastily concentrated the survivors of the Battle of Qaddasiyyah at Ctesiphon . Saad , when he came to know about the Sassanid detachments on the main route to Ctesiphon , decided to subjugate them . He accordingly organized a strong advance guard to overpower the Sassanid detachments ; the main army would join the advance guard shortly afterwards . For ease in movement he divided the rest of his army into four corps . Under the commanders Abdullah ibn Mutim , Shurahbeel ibn As Samt , Hashim bin Utba and Khalid bin Arfatah . Saad himself moved with the corps of Khalid bin Arfatah . From Qadisiyya , the main stages on the route to Ctesiphon were Najaf , Burs , Babylon , Sura , Deir Kab , Kusa , Sabat . The advance guard comprising all of the cavalry was put under the charge of Zuhra ibn Al - Hawiyya . Zuhra was directed to move to the main stages on the route to Ctesiphon and deal with the Sassanid detachments ; in case of encountering any large concentration of the Sassanid army , he was directed to wait until the main army arrived . The rest of the Muslim army was to move behind the advance guard at a comfortable pace . The corps of Zuhra set off as the advance guard . It occupied Najaf and stayed there till the other corps reached Najaf . Then Zuhra with his corps crossed the Euphrates and proceeded on the road to Ctesiphon . He reached Burs on the western bank of the Hilla branch of the Euphrates , where a small Sassanid force resisted ; the contingent was overpowered and retreated towards Babylon . Zuhra stayed at Burs waiting for main army to join him . The next stage was Babylon , a fortified city where , it was learned , there was a large concentration of Sassanid forces . Babylon lay on the far bank of the Euphrates . It was also a place of strategic importance and was the gateway of the Suwad , the land between the Euphrates and the Tigris . Some time in the middle of December 636 , the Muslims crossed the Euphrates and camped outside Babylon . The Sassanid forces at Babylon are said to have been commanded by Feerzan , Hormuzan , Mihran and Nakheerzan . It appears that there was disunity among the Persians , and they could not put up a stiff resistance against the Muslim charge . Hormuzan with his forces withdrew to his home province Ahwaz . On his withdrawal , the other generals also pulled back their forces and withdrew northward . After the Persian forces had left , the citizens of Babylon formally surrendered . They were afforded protection under the usual terms of payment of " jaziya " . Some volunteered to cooperate with the Muslims in their fight against the Sassanid regime . They furnished a good deal of useful information about the disposition of the Persian forces . Some Babylonian engineers are said to have been employed for the construction of roads and bridges . While the main Muslim army remained at Babylon , Zuhra was commanded by Saad to pursue the Persians who had retreated from Babylon , before they could concentrate effectively at some other place to give a combined resistance . The Muslim advance guard under Zuhra followed the Persians , and caught the Persian rear - guard at Sura , where the Sassanid forces were routed ; they retreated towards Deir Kab . Zuhra next marched to Deir Kab and defeated the Sassanid detachment again there . After which Deir Kab was occupied by the Muslims , and the people were afforded protection under the usual terms . Zuhra waited until the main army joined him at Deir Kab . Early in January 637 , the Muslim advance guard under Zuhra reached Kusa , ten miles from Ctesiphon , where Sassanid Persians were to make their last stand to delay the Muslim advance as much as they could . The Sassanid detachment there was commanded by Shahryar , who was killed in a duel with one of Muslim Mubarizun . The rest of the Sassanid army hastily withdrew to Ctesiphon , whereupon the Muslims occupied Kusa on the usual terms . After the victory , Zuhra stayed at Kusa for some time . In the meantime main army reached Kusa . Kusa was a place of historic importance to Muslims who believed that here Nimrod imprisoned the Prophet Abraham , who was thrown in burning fire , out of which he had emerged unharmed . Saad wrote a detailed account of the march towards Ctesiphon . In the second week of January 637 , the Muslim advance guard reached Sabat , four miles from Ctesiphon . It was a Persian cantonment , but there was no garrison there . The residents were given protection on the usual terms of payment of " jaziya " . Now the entire land up to the very gates of Ctesiphon belonged to the Muslims . Siege of Bahrseer . Ctesiphon the capital of Persia was not one city ; it was a conglomeration of several cities . Indeed the Arabs called Ctesiphon " Al - Madain " , meaning the cities . The main city lay on the eastern bank of the Tigris . The part of the city on the western bank of the Tigris was known as Bahrseer . The Muslim advance to Ctesiphon was delayed by the detachments placed on the route to Ctesiphon . That gave enough time to the Sassanids to arrange for the defense of the city , as Yazdgerd III planned . The Muslims were expected to follow the traditional route to Ctesiphon and expected to appear before Bahrseer ; for this purpose , Bahrseer had been well prepared for defense , and a deep ditch had been dug round the perimeter of the suburb . As the Muslim advance guard approached Bahrseer , the Persian garrison within the fortified city hurled stones at the Muslims through ballista s and catapult s . The Muslims pulled back beyond the range of the projectiles and laid siege to the city . The siege began in January 637 , and dragged on for two months . The supplies from the countryside on which Bahrseer depended were entirely cut off ; however it continued getting supplies from Ctesiphon across the Tigris . It was here that Muslims first used siege equipment made for them by the Persian engineers who had accepted the Muslim rule . Some time in March 637 , the Sassanid garrison called forth from the city in the determined effort to break the siege . Muslim chronicles record an interesting duel between a lion and Muslim commander Hashim , it is said that the Sassanid forces were led by a fierce lion which had been specially trained for war . The lion rushed at the Muslim front , and the Muslim horses bolted . Hashim bin Utbah is said to have rushed at the lion and delivered such a well directed blow that it fell dead . Saad the Commander - in - Chief of the Muslim forces stepped forward to kiss Hashim on the forehead as a mark of admiration for his act of unparalleled heroism . Exactly who commanded the Sassanid army there is not certain , however Muslim chronicles record that the Sassanid commander was killed in a duel by Zuhra . Later that evening Zuhra was stuck by an arrow and the hero of the march to Ctesiphon , died . He was buried with full military honors . After the break in fighting , a Persian emissary came to the Muslim camp to convey a message from the Persian emperor . The Persian emissary is reported to have said : Saad , however insisted on the usual term , " jaziyah " or the sword . Sassanid accepted the sword . With Ctesiphon prepared for defenses , Sassanid forces and residents of the Bahrseer withdraw to the main city the next day , destroying all bridges on the Tigris behind them . They had also taken away all the boats from the western bank of the Tigris , and anchored them on the eastern bank . Ctesiphon was guarded from its southern end by a natural barrier , river Tigris and by now a ditch had been dug surrounding rest of the suburbs . With these arrangements Yazdgerd felt satisfied that he could resist Muslims until he managed to get sufficient reinforcement from other provinces to break the siege . The Muslim forces occupied Bahrseer ; the town was empty . Capture of Ctesiphon . After the occupation of Bahrseer , only the Tigris , half a mile wide , lay between the Muslims and Ctesiphon . The river was in flood and there were no means with the Muslims to cross it . In their withdrawal from Bahrseer the Persians had taken away all the boats . The Sassanid forces in Ctesiphon were commanded by Generals Mihran and Khurrazad , brother of General Rostam who had been killed in the Battle of Qaddisiyyah . Thanks to the Persian volunteers who had accepted the Muslim rule , who showed a site downstream where the river could be forded . Saad saw the site , but was not sure whether it was fit for crossing . The next morning Saad asked for volunteers who could cross the river on horseback . First a band of six hundred volunteer horsemen under Asim ibn Amr plunged into the river to cross over to the other bank . A detachment of Sassanid cavalry was sent to intercept the approaching Muslims , and Sassanid horsemen also plunged in the river to hold back the Muslims from crossing the river . A river battle ensued . The Muslims cavalry however successfully overpowered the Persian cavalry and routed them and landed on the eastern bank of the Tigris . The first band of volunteers was immediately followed by other cavalry regiments . The infantry was probably brought to the eastern bank by the boats anchored on the shore . Sassanid forces were too few to offer an effective resistance against Muslims and thus evacuated Ctesiphon . From the river bank the Muslim forces marched to the city of Ctesiphon , led by the column of Asim ibn Amr . The Muslim columns marched through the heart of Ctesiphon . All business premises were closed . No Persians were seen , and the Muslims met no resistance . The Muslims reached the White Palace , the seat of the Persian government , and occupied it . The capital City of Sassanid Persian Empire was thus captured by the Rashidun army without any major battle . Aftermath . After occupying the city , Saad announced amnesty to all Persians who were in the city . A delegation of the representatives of the people waited on Saad . They sought terms , and the usual terms of " jaziya " were imposed . A regular peace pact was drawn up , and the citizens were called upon to follow their normal avocations . Sa ' ad moved into the White Palace and established his headquarters there . The great courtyard of the palace was converted into a mosque . Emperor Yazdgerd had retreated to Hulwan . While withdrawing the Persian emperor carried away as much of the imperial treasure and other valuable possessions as he could carry . Saad next sent out columns in several directions to deal with the Persian stragglers . A massive booty fell into the Muslim hands . Muslim forces conquered the Persian provinces as far as Khuzistan . The conquest however was slowed by a severe drought in Arabia in 638 and the plague in southern Iraq and Syria in 639 . After this Caliph Umar wanted a break to manage the conquered territories and for then he decided to suspend the offensive . Umar is reported to have said : The Sassanids continued the struggle to regain the lost territory . Thus a last standing Persian force was crushed at the Battle of Nihawand , fought in December 641 . The last Persian emperor Yazdgerd III was killed in 651AD during the reign of Caliph Uthman . With his death Sassanid Persian empire ceased to exist .