Britain colonized, as they do, and created Nigeria combining ~300 minor tribes, ~30 bigger tribes, and ~3 main tribes. The biggest are: Igbo, Yoruba, and Hausa/Fulani.
The North of Nigeria touches the Sahara. The South is close to the equator. Think of Nigeria as transitioning between 2 climate zones: The North, which is like California/Arizona weather, and the South, which is Florida / Georgia weather.
Much of Nigeria's oil deposits are under Igbo + Delta land.
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