Raja Dahir (663 – 712 CE) was the last Hindu^[1] ruler of Sindh (in present-day Pakistan).^[2] A Brahmin ruler,^[3] his kingdom was invaded in 711 CE by the Arab Umayyad Caliphate, led by Muhammad bin Qasim, where Dahir died while defending his kingdom. According to the Chachnama, the Umayyad campaign against Dahir was due to a pirate raid off the coast of the Sindhi coast that resulted in gifts to the Umayyad caliph from the king of Serendib (Old name of Sri Lanka) being stolen.^[4][5]

Raja Dahir was born in 663 CE into the Brahman dynasty of Sindh, a family deeply rooted in Hindu traditions and governance. His father, Chach of Aror, who ruled from 631 to 671 CE, was a Brahmin who ascended to the throne after marrying the widowed Queen Suhandi. This event established the Chach dynasty, which would rule Sindh for nearly a century.^[6]

He fought 3 battles successfully but was killed in the final one after being betrayed by the Buddhists who resented him during the Battle of Aror.^[7] He died defending his region at Sindh which took place between his dynasty and the Arabs at the banks of the Indus River, near modern-day Nawabshah at the hands of the Arab general Muhammad bin Qasim.^[8]

The Chach Nama is the oldest chronicle of the Arab conquest of Sindh. It was translated into Persian by an Arab named Muhammad Ali bin Hamid bin Abu Bakr Kufi in 1216^[9] from an earlier Arabic text believed to have been written by the Thaqafi family (relatives of Mukhtar al-Thaqafi).

Throughout his reign, Maharaja Dahir had to face invasions from the Umayyad Caliphate which had grown quite powerful by that time.

According to Chachnama and the Arab historian Biladhuri, Dahir defeated the Arabs twice in pitched battles during the twin battles of Debal in which the invading Arab commanders Ubaidullah and Budail or Bazil were killed by Sindhis under Dahir's son Jaisiah.^[10][11]

Jaisiah later appointed his own chief or Thakur who governed on his behalf. According to Chachnamah, when the news of Bazil's death was relayed to Hajjaj, he became very sad and full of rage.

This led to the fateful expedition by Muhammad bin Qasim. Before the Battle of Aror, Maharaja Dahir is said to have given this speech as per Chachnama^[11]

"I am going to meet the Arabs in open battle, and fight them as best as I can. If I crush them, my kingdom will then be put on a firm footing. But if I am killed honourably, the event will be recorded in the books of Arabia and India and will be talked about by great men. It will be heard by other kings in the world, and it will be said that Raja Dahir of Sindh sacrificed his precious life for the sake of his country, in fighting with the enemy."^[12]

The primary reason cited in the Chach Nama for the expedition by the governor of Basra, Al-Hajjaj ibn Yusuf, against Raja Dahir, was a pirate raid off the coast of Debal resulting in gifts to the caliph from the king of Serendib (modern Sri Lanka) being stolen.^[4] Meds (a tribe of Scythians living in Sindh) also known as Bawarij had pirated upon Sassanid shipping in the past, from the mouth of the Tigris to the Sri Lankan coast, and now they were able to prey on Arab shipping from their bases at Kutch, Debal and Kathiawar.

Hajaj's next campaign was launched under the aegis of Muhammad bin Qasim. In 711, bin Qasim attacked at Debal and, on orders of Al-Hajjaj, freed the earlier captives and prisoners from the previous (failed) campaign. Other than this instance, the policy was generally one of enlisting and co-opting support from defectors and defeated lords and forces. From Debal, bin Qasim moved on to Nerun for supplies; the city's Buddhist governor had acknowledged it as a tributary of the Caliphate after the first campaign and capitulated to the second. Qasim's armies then captured Siwistan and received allegiance from several tribal chiefs and secured the surrounding regions. His combined forces captured the fort at Sisam and secured the region west of the Indus River.

By enlisting the support of local tribes such as the Meds and also the support of the Buddhist rulers of Nerun, Bajhra, Kaka Kolak and Siwistan as infantry to his predominantly-mounted army, Muhammad bin Qasim defeated Dahir and captured his eastern territories which were added into the Umayyad Caliphate.^[13]

Sometime before the final battle, Dahir's vizier approached him and suggested that Dahir should take refuge with one of the friendly kings of India. "You should say to them, 'I am a wall between you and the Arab army. If I fall, nothing will stop your destruction at their hands.'" If that wasn't acceptable to Dahir, said the vizier, then he should at least send away his family to some safe point in India. Dahir refused to do either. "I cannot send away my family to security while the families of my thakurs and nobles remain here."^[13]

Dahir then tried to prevent Qasim from crossing the Indus River, moving his forces to its eastern banks. Eventually, however, Qasim crossed the river and defeated his forces at Jitor led by Jaisiah (Dahir's son). Qasim fought Dahir at Aror (near modern Nawabshah) in 711, eventually killing him. After Dahir was killed in the Battle of Aror on the banks of the River Indus, his head was cut off from his body and sent to Hajjaj bin Yousuf.

• Chach Nama
• Rai dynasty

• Raja Dahir's Wife Rani Bai fled to the fort of Rawar with 150,000 troops from where she challenged Muhammad Bin Qasim for the battle. Muhammad bin Qasim chased her to Rawar and ordered his miners to dig and demolish the walls of the fort until the bastions were thrown down. Rani Bai, however, finding herself encircled, surrendered and burnt herself along with other ladies.
• Mirza Kalichbeg Fredunbeg: The Chachnamah, An Ancient History of Sind, Giving the Hindu period down to the Arab Conquest. Translated by from the Persian by, Commissioners Press 1900 [2]
• R. C. Majumdar, H.C. Roychandra and Kalikinkar Ditta: An Advanced History of India, Part II,
• Tareekh-Sind, By Mavlana Syed Abu Zafar Nadvi
• Wink, Andre, Al-Hind the Making of the Indo Islamic World, Brill Academic Publishers, 1 January 1996, ISBN 90-04-09249-8