During Caliph Walid's rule (705-715) when Hajjaj Bin Yousuf was the governor of the Eastern part of the Umayyad Empire, an army was sent to conquer Sindh. The conquest became easy because Makran was already under the Arabs which made the land route safe. Moreover, it no more remained a safe haven for rebels.

Both Makran and Sindh were part of the Mauryan Empire during ancient times and due the efforts of Ashoka, these regions had been converted to Buddhism. However, Hinduism revived during the Gupta period and dominated society but in Sindh, Buddhism remained a popular religion till the 19th century and thus both religions, Hinduism and Buddhism, were followed by their respective factions peacefully.

Sindh's culture and society was quite different from those of North Indian. There was no sati tradition; neither was the caste system rigid nor was cow regarded as a sacred animal.

The major reason behind the Arab invasion of Sindh was the quest for a seaport in Indian Ocean. In 636AD too, Arabs tried to capture Thana and Bharoch but it was an unsuccessful attempt. The Arab traders had their settlement in South India and Gujarat and they had also got footing in the island of Ceylon. When pirates started to loot their ships, Arab traders wanted to have a safe passage and under these circumstances, Muhammad Bin Qasim invaded Sindh in 711-12 and conquered Debal, Sahwan, Brahmanabad, Aror (now known as Sukkur) and Multan and Sindh became a part of the Umayyas and Abbasid Khilafat. Governors were appointed to administer it. One of the advantages of Arabs' conquest of Sindh was that the sea became a safe place for traders to travel.

After this conquest, the Arabs set up their settlements in different parts of Sindh. New cities were founded, and social and cultural relations with the Arab world became strong. People of Sindh were divided into different tribes and all individuals were required to remain loyal to their respective tribes as an isolated person could not survive on his own. When some of the tribal leaders converted to Islam, their fellow tribesmen also followed them and accepted Islam. Jats, Meds and Soomro tribes were nomads who converted to Islam and later on adopted agriculture as their profession, which made Sindh a prosperous region.

After the decline of the Abbasid Caliphate, small Arab states emerged in Sindh — one of them was Habbari, whose capital was Mansura and in Multan, Banu Sama established its rule; both ruling dynasties were Ismailis. The Arab rule remained confined only to Sindh and Arabs did not make any attempt to attack other parts of India.