Specialty coffee thrives anywhere in the world where there are two things: A tropical climate and a high elevation. Fortunately, these conditions exist in more than 50 coffee-growing countries around the globe.
Obviously, soil is a major contributor here. In fact, geographical distinction is often called terroir, which is simply French for "soil." Volcanic soil, for example, has a reputation for contributing notes of citrus and chocolate.
However, there is much more to regional character than the content of the soil. A particular region may have an abundance of river water, for example. This would influence preferred ways of coffee processing –– or fruit removal from the seed –– since water is a crucial component in what is called the washing process.
Another factor is industrial infrastructure and its relationship to government. Some countries are highly socialized while others are less so. This will influence the way coffee is bought and sold and how producers make the most money. Some will, therefore, favor the cooperative model of regional blending while others will maintain the transparency which comes with single microlots from single farms.