"Verily, courage, and generosity and liberality,
Belonged to Muhammad, son of Qasim, son of Muhammad,
He led armies at the age of seventeen years,
He seemed destined for command from the day of his birth."
Arab Invasion of Sind (712): The rise of Islam in India began with the conquest of Sind (now in Pakistan) by the Arabs. At that time Sind was under the rule of a Hindu Brahmin dynasty with its capital at Alor. It was during the reign of Caliph Umar ibn Al-Khattab (634-644) that an army of Islam was first sent out to Sind to carry on religious wars. Sind was conquered during the caliphate of Al-Walid ibn Abd-al-Malik of Umayyad dynasty of Damascus (705-715). At that time the ruler of Sind was Rai Dahir, son of Chach.
Al-Hajjaj ibn Yusuf:
In 694 Abd-al-Malik (685-705) appointed Al-Hajjaj ibn Yusuf the governor of Iraq. Hajjaj, though nominally governor only of Iraq, in fact ruled all the countries which constituted the entire eastern frontier of the Umayyads. The king of Ceylon sent some valuable jewels and other articles as a present to Hajjaj in eight vessels that included Muhammadan orphans, Abyssinian slaves and female pilgrims. Their ship was attacked and plundered by some robbers of Debal (a region in Sind). One of the Muslim women exclaimed, "Oh Hajjaj! The robbers killed many of them and made others prisoners. Few people who had escaped made their complaint to Hajjaj. When this news reached Hajjaj, he replied, "I am here!" Hajjaj sent a messenger to Rai Dahir at Sind demanding their release, but Dahir replied that he had no sufficient strength to capture the robbers of Debal. Hajjaj first send Ubaidu-lla bin Nabhan and secondly Buzail against Debal, but both were killed. Meanwhile Abd-al-Malik died and was succeeded by his son Walid. Hajjaj wrote to Walid asking permission to conquer Sind; and this time Hajjaj sent his cousin and son-in-law Muhammad-bin-Qasim to invade Sind.
Muhammad-bin-Qasim, the Arab Conqueror of Sind:
Muhammad-bin-Qasim was a youth of seventeen when this important command was conferred upon him. He left Baghdad with six thousand Syrians to conquer Sind. There was at Debal a lofty temple crowned by a long pole, and on the pole was fixed a red flag, which when the breeze blew was unfurled over the city: The flag staff was brought down by a mangonel and the pole and the dome were broken into pieces. Seeing this people fled. Debal was captured and the Muslim prisoners were released. When this news reached Rai Dahir, he proposed to go to the borders of Indus to fight them but his nobles advised him to be patient, "The Arab force have come on account of the enemies of their religion: If they make excursions here and there, and in this way leave our country, it will be good; if not, we must be cautious, and we have to give them much money from the treasury, to save our country from their mischief". After taking Debal Muhammad Qasim began to capture the neighboring towns of Nirun, Sahban, Sadusan and Siwistan. After that he crossed the river Indus and marched to Alor against Rai Dahir. Then only Dahir realized his mistake that he had ignored every precaution not believing that the Arabs would dare to advance so far.
Death of Rai Dahir and capture of Alor:
Dahir fought valiantly in the battle and on the last day he came mounted on his elephant. Towards evening, one of Qasim's men threw a naphtha arrow at the litter of Rai Dahir's elephant and the litter soon caught fire. The elephant fled towards the river and sat down in the mud. The Arab archers continuously shot arrows at Dahir, one of which pierced his throat and he fell down in his litter and died. The Brahmins who were in the litters on the elephants behind him took him out of his seat and hid his dead body in the mud, then fled. But in the morning these Brahmins were captured by an Arab general. Qasim ordered the body of Rai Dahir to be taken out. When Dahir's body was taken out from mud it was still smelling the sweet scent of musk and attar of roses! Dahir's head was cut off and fixed on a lance.
Qasim want to capture the fort of Alor and he sent the head of Dahir to the people in front of the fort. Rani Ladi, wife of Dahir, seeing his head went out weeping. The people opened the gate and the fort was captured. With the conquest of Sind Hajjaj got possession of immense wealth along with elephants, horses and cattle. Hajjaj had spent sixty millions of dirhams for this expedition and the wealth he got from Sind amounted to one hundred and twenty millions!
Capture of Rawar and Rani Bai Commits Jauhar: When Qasim marched against Raor (Rawar), Rani Bai, the sister of Rai Dahir, committed jauhar. (When Dahir ascended the throne, astrologers predicted that her husband will be the king of Sind. For this reason Dahir married his sister, but there was no consummation).
After the capture of Brahmanabad Muhammad Qasim wrote letters to the rulers of Hind asking them either to accept Islam or pay a tribute escaping from war. In this way he advanced as far as Kannauj.
Death of Muhammad-bin-Qasim:
Tarikh-i-Masumi and Chachnama give an interesting account of Muhammad-bin-Qasim's death; according to which Caliph Walid was responsible for his death. Qasim had sent to the Caliph Soorya Devi and Parmal Devi, two virgin daughters of Rai Dahir, who were seized after the capture of Alor. Enamored of her surpassing beauty the Caliph ordered Soorya Devi to stay in his room at night. The girl replied that she's not fit for the bed room of the Caliph because the just amir Muhammad Qasim had kept both of them for three days before sending them to the Caliph. She said that such a disgrace should not be permitted by kings. The Caliph immediately wrote a letter to Qasim that he should wrap himself up in the raw hide and be present at the capital. Muhammad Qasim was at Udaipur when he received this letter. Qasim ordered his men to put him into a hide, place in a chest and sent him to the capital. In this way died Muhammad-bin-Qasim.
When the box was taken to the Caliph, he opened it and showed the corpse to the girls, telling them that how strictly his commands were obeyed. Soorya Devi at first made apologies and then accused the Caliph for not making proper enquiries before passing such an order. She said, "in fact Muhammad Qasim was like a brother to us and he never touched us. We have told you false things about him for taking our revenge as he killed our father, desolated the kingdom of our fathers and grandfathers, and degraded us from princely rank to slavery. As for Muhammad Qasim, if he had any sense in him he would have reached here in the usual way and then enclosed himself in raw leather, so that after finding out the truth he would not have died. She also added that Muhammad Qasim, who defeated the king of Sind, captured many towns, built mosques and minarets and captured a hundred thousand slave girls, should not have been killed simply on the words of a slave girl. Hearing this the Caliph ordered the two sisters to be buried alive in a wall (Chachnama). According to Tarikh-i-Masumi, he ordered that the two girls were tied to the tails of two horses, and after having been dragged round the city, they were thrown into the Tigris.
Futuh al-Buldan gives a more reliable account and according to which Muhammad Qasim was made prisoner and tortured to death by the order of Caliph Sulayman. "Hajjaj died in 714; upon learning this, Muhammad left Multan and returned to Alrur and Baghrur, which had been previously captured. He sent an army towards al-Bailaman and its inhabitants surrendered without any resistance. He made peace with the inhabitants of Surast with whom the men of Basea are now at war. Then he went against the town of Kiraj. Duhar advanced to oppose him, but the enemy was put to flight. After the death of Walid (715), his successor Sulayman appointed Salih the governor of Iraq. Yazid was made governor of Sind and Muhammad Qasim was sent back a prisoner with Mu'awiya. The people of Hind wept for Muhammad and preserved his likeness at Kiraj. He was imprisoned by Salih at Wasit. Salih tortured him together with other persons of the family of Abu' Ukail until they expired, since Hajjaj had put to death Salih's brother Adam".
The Umayyads were the first Muslim dynasty.
About the Hindu Kings of Sind: Rai Dewaij → Rai Sahiras I → Sahasi I → Rai Sahiras II (His dominions extended on the east to Kashmir and Kannauj, on the west to Makran, on the south to the coast of the sea and Debal, and on the north to the mountains of Kurdan and Kikanan. He was defeated and killed by king Nimruz) → Rai Sahasi II → Chach (The Brahmin Chach who usurped the kingdom was Rai Sahasi II's chamberlain) → Chandar, brother of Chach → Rai Dahir, son of Chach
Tarikh-i-Masumi, A history of Sind, embracing the period from A.D. 710 to A.D. 1590 by Muhammad Masum translated by George Grenville
Futuh al-Buldan by Al-Baladhuri translated by H. M. Elliot
The Chachnamah - An Ancient History of Sind written in Persian by Ali son of Muhammad Kufi, translated by Mirza Kalichbeg Fredunbeg