The war started mainly because of four aspects: Militarism, Alliances, Imperialism and Nationalism. ... The alliances system meant that a local conflict could easily result into an intimidating global one. The overall cause of World War was the assassination of Archduke Franz Ferdinand.
I'd say they developed in river valleys (2).
The legal right to expatriation means that <span>you have the right to renounce your citizenship. Just as an immigrant has the right to petition for a citizenship.</span>
