Some scholars believe that Hanno the Navigator's expedition beyond the Pillars of Hercules went as far as the Senegambia region, or perhaps even as far as the Gulf of Guinea. Hanno's Periplus reports his establishment of several colonies along the way, the furthest being "Cerne" which has never been conclusively identified with a modern location.
What if Hanno set up a successful Carthaginian colony in the Senegambia area, perhaps around OTL Dakar? How could we get it to survive in some form, and what are some options?
Might the Carthaginians become more oriented on West Africa rather than on Europe? Could the Carthaginian government relocate there should the Romans still defeat it? Could the colony maintain its independence from the Roman Empire, or would its presence attract Roman interests? What impact could such direct Mediterranean trade and influences have on the development of native West African civilizations, and what would happen in the vicinity after the settlement inevitably loses its Mediterranean character?
I've been trying to read up on the prehistory of Senegambia but it's a bit difficult. All I can seem to find is that there is evidence of human habitation in the area long before this period, but modern Senegambian ethnic groups like the Wolof didn't show up until much later, around the 11th century CE. I can't seem to find any references confirming when agriculture was introduced to the region.