The Arabs remained. There were some political and economic reasons that motivated many Arabs and their subjects to penetrate Sudan, as well as to work in the mining mines in the Eastern Desert, to call for Islam, to engage in Indian trade, and to transport pilgrims across the desert to the port of Aidhab via the ports overlooking the Red Sea.

The call to Islam and the spread of that message, which the Arabs left the Arabian Peninsula to spread, was one of the strong reasons for moving south, in addition to the commercial factor. The Arabs were people of trade, "the journey of winter and summer," which was one of the strong reasons for penetrating south through the land of Marwa and Alwa, which were still Christian states, during the early centuries of the Islamic call. They engaged in commercial activities in addition to calling for the religion of the eternal God. They brought food, clothing, and pottery and returned with ostrich feathers, goats, and livestock. These activities were part of this commercial activity, as the demand for products from these regions increased in the Islamic world. Especially since the commercial factor was one of the reasons for the Islamic infiltration to the south, as trade was regulated by the Treaty of Baqt, concluded in 31 AH / 651 AD between the ruler of Dongola and the governor of Egypt, Abdullah bin Saad bin Abi Sarj. This treaty laid down the rules and principles. This treaty recognized the freedom of passage for merchants between the two regions, "provided that you enter our country passing through, not residing in it, and we enter your country passing through, not residing in it, and you are responsible for those who reside in your country or pass through it, whether Muslim or a treaty holder, until they leave you."

This means that Muslim merchants and Islamic da'wah workers could enter the land of Nubia and establish themselves as non-resident traders, and their property and lives would be safe, even though some Arabs did not adhere to the provisions of this agreement and settled permanently after moving from one country to another.

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