Articles and geography

In the movie we saw last night about Bela Fleck taking the banjo back to its African context (which was very moving and deserves more than the off-hand mention it gets here), it struck us that the country we thought of as “Gambia” is actually “The Gambia”. Which led to a brief bit of research into what other countries have a “The”. Officially, just The Bahamas. Unofficially, Ehren decided, it should be all countries that start with “United”, plus all plural island chains.