Answer:
Songhai was invaded, because Morocco wanted to own its mines of gold.
Step-by-step explanation:
In the north of the African continent, the Saadian sultanate in Morocco was at the height of its power. On August 4, 1578, the forces of the Moroccan Sultan, at the head of 50,000 men, had defeated the Portuguese troops with 16,000 men commanded by King Sebastian in Alcacer-Quibir. The victory, however, sold out of the country leaving Morocco on the brink of bankruptcy. In search of new resources for his kingdom, Sultan Ahmad al-Mansur Saadi turned his attention to the Songhai Empire where he coveted to take possession of the fabulous gold mines.
The Songhai cavalry was massacred by the Moroccan firearms. Djudar entered Gao and plundered the city, but found little wealth. He went to Tombuctu and Djenné to plunder them as well.
The Songhai Empire collapsed and never rose again. However, Morocco proved unable to exercise firm control over the area due to the vastness of the Sonhai domains and communication difficulties. A decade of sporadic fighting began and the territory eventually split into dozens of smaller kingdoms.