The Sultanate of Kilwa was a powerful city-state located on the eastern coast of Africa, primarily in present-day Tanzania. It flourished from the 9th to the 16th century and became a significant trading hub in the Indian Ocean. Kilwa was known for its wealth, which came from trade in gold, ivory, and spices, connecting Africa with the Middle East and Asia. The sultanate was ruled by a series of sultans who established a rich culture and impressive architecture, including the famous Great Mosque of Kilwa. The decline of the Sultanate began in the late 15th century due to Portuguese exploration and trade disruptions, leading to its eventual fall.