The Serbs and the Croats were, as regards race and language, originally one people, the two names having merely geographical signification. In course of time, for various reasons connected with religion and politics, the distinction was emphasized, and from a historical point of view the Serbo-Croatian race has always been divided into two. It is only within the last few years that a movement has taken place, the object of which is to reunite Serbs and Croats into one nation and eventually into one state. The movement originated in Serbia, the Serbs maintaining that they and the Croats are one people because they speak the same language, and that racial and linguistic unity outweighs religious divergence. A very large number of Croats agree with the Serbs in this and support their views, but a minority for long obstinately insisted that there was a racial as well as a religious difference, and that fusion was impossible. The former based their argument on facts, the latter theirs on prejudice, which is notoriously difficult to overcome. Latterly the movement in favour of fusion grew very much stronger among the Croats, and together with that in Serbia resulted in the Pan-Serb agitation which, gave the pretext for the opening of hostilities in July 1914. The designation Southern Slav (or Jugo-Slav, _jug_, pronounced yug, = _south_ in Serbian) covers Serbs and Croats, and also includes Slovenes; it is only used with reference to the Bulgarians from the point of view of philology (the group of South Slavonic languages including Bulgarian, Serbo-Croatian and Slovene; the East Slavonic, Russian; and the West Slavonic, Polish and Bohemian).