Fernando Poo is an island 32 km off the west coast of Africa, specifically Cameroon, in the Gulf of Guinea. Much of the action of the trilogy is centred around a coup d'etat on the island which is a trigger for nuclear war.
The Coup of Fernando Poo is carried out, in 1973, by Captain Ernesto Tequilla y Mota who consults Luttwak's Coup d'Etat: A Practical Handbook to do so.
The (fictional) anthropologist of the book, J.N Marsh, claims that certain artefacts found on Fernando Poo prove the existence of atlantis.
In the book the name of the island is changed from Po to Poo, why this is is not certain, it could be down to a spelling error. The relevance of the original spelling would indicate that it should be kept as Po because the I-ching Po (23) is a signifcant symbolic part of the book, indicating the increasingly chaotic political circumstances of the plot, it could be that adding the extra 'o' brings attention to the significance of the word itself.