This article uses an in-universe perspective.
Cuba, officially called the Republic of Cuba, is a socialist country located in the Carribean, just south of the U.S. state of Florida.
World War Z Edit
During World War Z, nearly every nation on Earth was pushed to the brink of extermination by the Zombie Hordes. However, some people, countries, and animals actually benefitted from the War by using large masses and terrain as profitable, vital materials. Countries such as Ireland, Denmark, Multiple islands in the Pacific, Tibet, Greenland, and especially Cuba actually thrived and became stronger than before the War, gathering large economic strength along with political reform. However, out of all of these, Cuba, which at one point was the second poorest nation in the Caribbean, actually became the richest country in the postwar world.
Cuba provided an ideal refuge for many reasons. Aside from the surrounding Carribean waters buying them time to prepare, their lack of diplomatic ties to the United States, their militaristic dictatorship, and their generally well educated populace (in addition to the millions of Cuban Americans returning to their country of their ethnicity), helped to resist the initial waves of zombies. Early outbreaks through transforming refugees were handled early and in brutal fashion. Their shorelines were quickly fortified. While Cuba was by no means spared the heavy fighting all survivor nations saw, their early success bred more success. The strength and stability (and to a certain extent, the beauty and climate of the island) made it a virtual jewel in a world of death. Cuba's warm climate allowed it to quickly switch from cash crops to sustenance farming - in contrast to survivors in other parts of the world who fled above the snow line, in places like Canada, Siberia, and Iceland, where starvation and cannibalism soon set in.
Soon, it attracted more specialized workers and talent, while harshly screening out undesirables. Before long, Cuba was one of the world's most powerful nations.