Abdallah ibn Amir

Map of Sakastan under the Sasanians

Having secured his position in Kerman, Abdallah sent an army under Mujashi ibn Mas'ud there. After crossing the Dasht-i Lut desert, Mujashi ibn Mas'ud reached Sakastan, but suffered a heavy defeat and was forced to retreat.[5] Abdallah also sent Rabi ibn Ziyad Harithi. After some time, he reached Zaliq, a border town between Kirman and Sakastan, where he forced the dehqan of the town to acknowledge Rashidun authority. He then did the same at the fortress of Karkuya, which had a famous fire temple, which is mentioned in the Tarikh-i Sistan.[6]

One year later, Abd-Allah ibn Amir sent an army under Rabi ibn Ziyad Harithi to Sakastan. After some time, Rabi reached Zaliq, a Sakastani border town, where he forced the dehqan of the town to acknowledge Rashidun authority. He then did the same at the fortress of Karkuya, which had a famous fire temple mentioned in the Tarikh-i Sistan.[6] He then seized more land in the province. Next, he besieged the provincial capital, Zrang, and, after a heavy battle outside the city, its governor, Aparviz, surrendered. When Aparviz went to Rabi ibn Ziyad to negotiate a treaty, he saw that Rabi was using the bodies of two dead soldiers as a chair. This horrified Aparviz, who, in order to spare the inhabitants of Sakastan from the Arabs, made peace with them in return for a heavy tribute of 1 million dirhams, including 1,000 slave boys (or girls) bearing 1,000 golden vessels.[6][7] Rabi ibn Ziyad was then appointed governor of the province.[8]

Estakhr was made into ruins after the battle and a force of 40,000 defenders including many Persian nobles were killed. After the Arab conquest of Pars, Yazdegerd fled to Kirman while being pursued by an Arab force.[7]

Abdallah invaded Pars and put an end to the Persian resistance.

Later, Abdallah sent Ahnaf ibn Qais and Amr ibn Ma'adi Yakrib in further expansion towards Persian territory Muslim conquest of Khorasan, to expand and subdued the cities of Marw al-Rudh and Balkh.[9] As winter came, Ahnaf and Amr stayed in Balkh.[9]

In its first conquest of Kerman, the Rashidun caliphate sent two contingents tasked with conquering Kerman, consisting of Ibn Amir and Suhail, who reached Tabasayn. Then, they advanced towards Nishapur. Ibr Amir and Suhail quickly met opposition, with fighting against the Koch o Baloch, resulting in the death of the governor of Kerman.

In 647 AD, Abu Musa al-Ash'ari was deposed from the governorship of Basra. Uthman appointed Ibn Amir as the Governor of Basra following the deposition. Ibn Amir was twenty-five years old at that time.

During his tenure as governor in Basra, Ibn Amir changed the town from a merely transient camp to a permanent settlement, and gradually become center of commercial in Iraq. While he undergoing further conquest to the east, Basra gradually also started to lose her characteristic as a frontier garrison.[12]

Uthman was aiming to solve tensions in newly-conquered Iraq caused by the sudden influx of Arab tribesmen into garrison towns along the frontlines like Kufa and Basra. He did so by opening new fronts in territories he aimed to conquer. This aimed to consume and channel the tribesmen's energy towards new military expeditions. When Ibn Amir arrived at Basra, he immediately prepared the fronts for new conquests into Persia.[13][14] Ibn Amir reformed Basra in many ways, including the construction of a new irrigation canal and fixing the water supply infrastructure for the use of Hajj pilgrims passing through.[15]

During Uthman’s reign, the province revolted alongside other Persian provinces. Uthman directed Ibn Amir to crush the rebellion.

Accordingly, Ibn Amir marched his forces into Persepolis, which surrendered and agreed to pay tribute. From there, the army marched to the city of Al j bard, where it encountered small resistance. The resistance was quenched, and its citizens agreed to pay tribute. Afterwards, Ibn Amir advanced to Gor. The Persians fought against his force, but they were defeated and the city was captured. Peace was made in the term of Jizya.[4] While the army was still in Gor, Persepolis again revolted. Ibn Amir brought his forces to back to Persepolis and laid siege on the city. After a violent battle, Ibn Amir's army was able to regain control of the city. All Persian leaders guilty of instigating the revolt were captured and executed. With the fall of Persepolis, other cities in Fars also surrendered unconditionally. The Uthman-appointed governor of Pars, after analyzing the situation, sent Islamic missionaries to various cities in the region to convert the people to Islam, with the hopes of avoiding future revolts lead by Persian nationalism.

After suppressing revolts in Fars, ibn Aamir turned towards Kerman, which revolted again in 651-652 AD. He sent a force under the command of Mujasshaa ibn Musa Salmi. Kerman was soon re-conquered with little resistance.[16]

Uthman directed ibn Aamir, who at the time was Governor of Basra, to re-conquer the province. A column was sent to Sistan under Rabeah ibn Ziyad's command. He re-conquered the area up to what is now Zaranj in Afghanistan. Ibn Ziyad was made governor of Sistan, where he remained for years, then left for Basra, whereupon the province broke into revolt once again, this time over a much larger area.

Ibn Aamir sent Abd al Rahman/Abdur Rahman ibn Sumra to implement the operation. Ibn Sumra led the Muslim forces to Zaranj. Once Zaranj was captured. Abd al Rahman marched into Afghanistan and conquered it northward up to Kabul. After this campaign ibn Aamir set his eyes toward Khorasan.

Khorasan, a province of the Persian Empire was conquered during the reign of Caliph Umar, under command of Ahnaf ibn Qais. After Caliph Umar's death, Khorasan broke into series of which first happened when revolt under Persian Emperor Yazdegerd III, but before he could lead the Persians against the Muslims, he was betrayed and killed in 651. Caliph Uthman in 651, sent ibn Aamir, governor of Basra, to re-conquer Khorasan. Ibn Aamir marched with large forces from Basra to Khorasan outstripping another contingent of Said Ibn Al-Aas, who departed from Kufa together with Hudzaifah Ibn Al-Yaman, Husayn ibn Ali, Hasan ibn Ali and other companions.[17]

After capturing the main forts in Khorasan he sent many columns to various directions into Khorasan in order to prevent the Persians from gathering into a large force.[4] The town of Bayak, in modern Afghanistan, was taken by force, with a Muslim commander falling in the battle. After Bayak, the Muslims marched towards Tabisan, which was captured with little resistance. The Muslim army captured the city of Nishapur after a long siege. The Muslim army continued capturing other small and big towns in the Khorasan region. Afterward, they consolidated their position in Khorasan. The Muslims then marched towards Herat in Afghanistan, which surrendered to Muslims peacefully. After gaining control of the region the Muslims marched towards the city of Merv in modern Turkmenistan. The city surrendered along with other towns of the region except for one, Sang, which was later taken by force. The campaign in Khorasan ended with the conquest of Balkh (Afghanistan) in 654.

However, the second uprising was broken again in Khorasan after the wake of The First Muslim civil war when Muawiya was appointed as Caliph replacing Ali, this time happened in Herat and Balkh. Abdullah was appointed once again to give reprisal of this revolt. This time the retaliation was fierce and swift where the famous Zoroastrian temple of Nobahar was destroyed.[18]

Because of the continuous campaign in Khorasan, there's an unavoided effect of Arabizations of this area under the military operations of Abdullah. it was described the structure of the army of Abdullah Ibn Amir during the reconquest of Khorasan was composed of the army from Basra which recruited from tribes which have Hijra (emigrated) to a Misr (garrison town) and enlisted in Diwan. It was natural that these tribesmen carrying on their old tribal traditions, bearing the name of their original clan('Ashira) with whom they might have severed their relationship by emigrating to the Misri. Each clan or even a tribal grouping from related clans would have its chief as commander. This is the military system which latter will standardize in the era of the Umayyad Caliphate[19]

After consolidating Muslim forces in Khorasan, Abdullah ibn Aamir crossed the Oxus River or more known to the Muslims as the Amu Darya and invaded Uzbekistan in southern Transoxiana. Details of these campaigns are little known but it is known that a greater part of southern Transoxiana submitted to the suzerainty of the Rashidun Caliphate.[4]

• Naji, A. J.; Ali, Y. N. (1981). "The Suqs of Basrah: Commercial Organization and Activity in a Medieval Islamic City". Journal of the Economic and Social History of the Orient. 24 (3): 298–309. doi:10.2307/3631909. JSTOR 3631909. Retrieved 27 October 2021.
• Morony, M. (1986). "ʿARAB ii. Arab conquest of Iran". Encyclopaedia Iranica, Vol. II, Fasc. 2. pp. 203–210.
• Marshak, B.I.; Negmatov, N.N. (1996). "Sogdiana". In B.A. Litvinsky, Zhang Guang-da and R. Shabani Samghabadi (ed.). History of Civilizations of Central Asia, Volume III: The Crossroads of Civilizations: A.D. 250 to 750. ISBN 92-3-103211-9.
• Zarrinkub, Abd al-Husain (1975). "The Arab conquest of Iran and its aftermath". The Cambridge History of Iran, Volume 4: From the Arab Invasion to the Saljuqs. Cambridge: Cambridge University Press. pp. 1–57. ISBN 978-0-521-20093-6.