Costa Rica is a small country in Central America. It is bordered by Nicaragua to the north and Panama to the south. It is notable for being one of a very few nations in the world with no armed forces.
During World War II, Costa Rica was aligned with the Allied Forces. It (along with the rest of Central America) was conquered by the Race's Conquest Fleet during their invasion of the Earth in 1942. It was recognized as a Race colony after the Peace of Cairo in 1944.
In this novel, Costa Rica is part of a much larger Guatemala, a province of Nueva España.