His killer wanted to unite all Serbs under one government not Austria.The Austrians wanted to punish Serbia plus the alliance system pulled one nation after another into the war.
The biggest difference in this period in the spreading of this two groups was that the Jews were forcefully spread out from their homeland to mainly the European countries even though they didn't wanted that, while the Christians systematically forced their way into the European continent even though it was under fire for few hundred years and forbidden for practice.