Bosnia and Herzegovina consists of two main sub-national political entities. Intuitively one might expect one to be called Bosnia and the other Herzegovina. But that is not the case.
The largest entity, some 26,000 square km in extent, is the Federation of Bosnia and Herzegovina, in common parlance usually referred to as the Bosniak-Croat Federation, reflecting the fact that its population consists mainly of Bosnian Croats (who are in the main Roman Catholic) and Bosniaks (who are predominantly Muslim). This entity is sometimes called the Muslim-Croat Federation or even just simply the Federation. The second entity, with about 24,000 square km only slightly smaller than the Federation, is the Republika Srpska. Occasionally, you’ll run across the name rendered as the Bosnian Serb Republic. The Brcko District, a tiddler with just 500 square km and the subject of an article in hidden europe 26, is nominally a condominium shared by both entities, but in practice it runs its own affairs.