Answer: The Aztec Empire was an alliance of three Nahua city-states: Mexico-Tenochtitlan, Tetzcoco, and Tlacopan. The three city-states ruled that area in and around the Valley of Mexico in 1428 until the forces of the Spanish conquistadores and their native allies who ruled under Hernán Cortés defeated them in 1521. The Ghana Empire, also known as Wagadou (Arabic: غانا) or Awkar, was a West African empire based in the modern-day southeast of Mauritania and western Mali that existed from c. 300 until c. 1100. The Empire was founded by the Soninke people, and was based in the capital city of Koumbi Saleh.
(some of this is according to wikipedia)