Which Southern African nation, formerly known as South-West Africa, gained independence in 1990 after years of South African administration and a protracted liberation struggle, and possesses significant diamond and uranium reserves?

1. Its capital city is Windhoek.
2. It's home to the Namib Desert, one of the oldest deserts in the world.
3. The Fish River Canyon, the second largest canyon in the world, is located here.
4. The official language is English, but Afrikaans and German are widely spoken.