Answer:
trans-Saharan trade
Explanation:
The trans-Saharan trade between the year 400 CE to 1000 CE has the biggest impact on west African kingdoms.
This trans-Saharan trade involves various exchanges of goods between West African kingdoms and North Africa and the Arabian people. Some of these goods are gold, ivory, salt, cloth, horses, books, swords, chain mail, and slaves.
Also, Africans were influenced by the language and religion of the people of Arab at the time.
