It was Common for Magrib Berbers to marry Soninke women

“Scholars have attributed Ghana’s political hegemony to the ruler’s ability to unify Soninke villages and maintain a cohesive confederacy of chiefs under the command of one king. Ongoing raids launched by North African Berbers searching for gold and slaves also served to maintain Ghana’s unification.”

“Though many North African groups raided the kingdom throughout its existence, Ghana developed alliances with one Berber people—the Magrib. Many Magrib Berbers established trade relations with Ghana chiefs and lived among their allies. Several trading posts were established in the Soninke villages near Kumbi, the main center of Ghana, as well as in the south and north of the Gambia River. (Levtzion 1973:24, 28, 104).”

“Other major Ghana trading posts included in Timbuktu, Wagadugu, Gundiuru, and Awdaghustic. Magrib Berbers traded horses, brass, copper, glassware, beads, leather, textiles, tailored clothing, and preserved food to the Soninke in exchange for gold, ivory, cloth, and preserved food to the Soninke in exchange for gold, ivory, cloth, pepper, kola nuts, and sometimes slaves.”

“In these trading centers, it became common for Magrib Berbers to marry Soninke women. Furthermore, the alliances between Ghana chiefes and Magrib Berbers helped Ghana retain its domination over Malinke and Songhay villages; when revolts erupted, the Magrib Berbers assisted their allies. By A.D. 1076 the Magrib Berbers demanded that the Soninke people convert to Islam (Levtzion 1973: 44; Oliver and Fagan 1975:166). The King of Ghana complied, yet many villages resisted.”

“The pressures to convert increased when Sanhaja tribes from various regions of North Africa united in a religious movement to convert people to Islam and attack those who resisted. The Sanhaja, like the Berbers, was a racially mixed Hamitic people, who were unified under the religious Almoravid Movement, centered in Morocco. Unlike the Magrib Berbers, the Sanhaja were enemies of Ghana and took over some of the Magrib Berber trading posts.”

“Many Soninke villages converted to Islam as a means of averting Islamic attacks. This did not stop the Sanhaja from demanding tribute from Ghana villages and taking people as slaves. By A.D. 1250 the Almoravid Movement had provoked conflict and religious factionalism in the Kingdom of Ghana (Levtzion 1973:51; Oliver and Fagan 1975:169). Most Ghana chiefs refused to convert to Islam and instead chose to end the Confederacy.

“Many successor states emerged out of Ghana. By this time a large part of West Africa had converted to Islam.”

“The Soso, who had been conquered by Ghana, emerged as the most powerful kingdom. They conquered many Soninke villages and also began preying upon the Malinke villages, which were not unified under one kingdom. Some Malinke villages were able to retain their independence and were subsequently unified by a man called Sundjata. Sundjata then launched a successful military campaign against the Soso people and replaced them as the military power of West Africa.”

“By A.D. 1250 Malinke chiefs had united in a confederacy, with Sundjata as their king (Oliver and Faga 1975:169). Sundjata’s clan, the Keith, became the ruling family, and his confederacy evolved into the Kingdom of Mali. The power of the Kingdom of Mali expanded, and it came to encompass the entire region that had formerly been Ghana. The Malinka also conquered the peoples from the Kingdom of Songhay.”