Muhammad bin Qasim was orphaned as a child and thus the responsibility of his upbringing fell upon his mother. She supervised his religious instruction herself, and hired different teachers for his worldly education. It was the uncle, Hajjaj bin Yousaf, who taught him the art of governing and warfare.

Qasim was an intelligent and cultured young man who at the age of fifteen was considered by many to be one of his uncle's greatest assets. As a show of faith in his nephew's abilities, Hajjaj married his daughter to Qasim. At the age of sixteen, he was asked to serve under the great general, Qutayba bin Muslim. Under his command Muhammad bin Qasim displayed a talent for skilful fighting and military planning. Hajjaj's complete trust in Qasim's abilities as a general became even more apparent when he appointed the young man as the commander of the all-important invasion on Sindh, when he was only seventeen years old. Muhammad bin Qasim proved Hajjaj right when he, without many problems, managed to win all his military campaigns. He used both his mind and military skills in capturing places like Daibul, Raor, Uch and Multan. History does not boast of many other commanders who managed such a great victory at such a young age.

Besides being a great general, Muhammad bin Qasim was also an excellent administrator. He established peace and order as well as a good administrative structure in the areas he conquered. He was a kind hearted and religious person. He had great respect for other religions. Hindu and Buddhist spiritual leaders were given stipends during his rule. The poor people of the land were greatly impressed by his policies and a number of them embraced Islam. Those who stuck to their old religions erected statues in his honor and started worshiping him after his departure from their land.

Muhammad bin Qasim was known for his obedience to the ruler. Walid bin Abdul Malik died and was succeeded by his younger brother Suleman as the Caliph. Suleman was an enemy of Hajjaj and thus ordered Qasim back to the kingdom. Qasim knew of the animosity between the two. He was aware that due to this enmity, he would not be well treated. He could have easily refused to obey the Caliph's orders and declare his independence in Sindh. Yet he was of the view that obeying ones ruler is the duty of a general and thus he decided to go back to the center. Here he became a victim to party politics. He was put behind bars where he died at age of twenty. Many historians believe that had he been given a few more years, he would have conquered the entire South Asian region.