Number 1: 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. Nationalism was a great cause of World War one because of countries being greedy and not negotiating. #2: Germany refused, so Britain declared war on Germany on Aug 4. ... In conclusion, the Alliance System was an important cause of the WWI because it divided the European powers into two rival military camps, the Triple Alliance and the Triple Entente, that the rivalry between the two camps brought about the war.
