Earthquakes in New Zealand occur because we are located on the boundary of two of the world's major tectonic plates – the Pacific Plate and the Australian Plate. These plates are colliding with huge force, causing one to slowly grind over, under or alongside the other.
Slavery ultimately led to the United States Civil War.
Both groups are called Slavs. In the years before World War I, Serbia wanted all Slavic peoples to form one empire, free from rule by the Turks or Austria-Hungary. The Serbs' wish to unite all the Slavs in one empire is an example of. imperialism.