During the West-African golden age [14th – 15th century] the Songhai Empire emerged, from the skeleton of the Mali Empire, to dominate the western region of the continent.
During the gradual decline of the Mali Empire [ca. 1230 – 1670], the ruling elite of the Songhai people saw a chance at greatness and launched their own military campaign against the Mali dynasty. As a result, Sunni Ali [in 1464 AD] rose to power and became the first ruler of the Songhai Empire.
Sunni Ali, one of the most effective military strategists to have ever lived, continuously expanded the Songhai Empire. At its height, the Songhai Empire covered what is now modern-day Gambia, Senegal, Niger, and Northern-Nigeria. Because of the wide territory it covered, the Songhai Empire is often referred to as the largest and wealthiest empire to have emerged in West-Africa.
The Sunni dynasty was later replaced by the Askia dynasty founded by Askia Muhammed the first, who later became known as Askia Muhammed the Great. Askia continued the expansion of the Songhai Empire in all directions within West-Africa and officially converted the Songhai Empire into an Islamic state.
The Songhai Empire used a complex governing system consisting of numerous ministers in different areas of governing, that made sure that the empire and its [autonomous] provinces were being well maintained. During the Askia dynasty, the fabled Timbuktu was re-established as the center of learning in the world. The Songhai Empire heavily funded institutions of learning [Quranic schools] that were producing scientists, historians, jurists, and scholars. Continuing the trend of learning initially started by the Mali Empire.
The success of the Songhai Empire was shortlived and fell into a gradual decline after the death of Askia the Great. Multiple power grabs by sons of Askia, political chaos and numerous civil wars made the Songhai empire an easy target for a foreign invasion.