The Croats of Bosnia and Herzegovina, often referred to as Bosnian Croats, are the third most populous ethnic group in that country, after Bosniaks and Serbs and are one of the constitutive nations of Bosnia and Herzegovina. They are a native ethnic group of Bosnia and Herzegovina. Croats of Bosnia and Herzegovina have made significant contributions to the culture of Bosnia and Herzegovina. Their mother tongue is Croatian, and most identify as Roman Catholic, although there is a small minority of atheists.