Summary | The First World War
The creation of a unified Italy and Germany altered the balance of power in Europe in the 1860s and 1870s. Nationalism, imperialism, great-power alliances, and public opinion—influenced by newspapers and photos—helped fuel tensions. By the early 1900s the Triple Alliance and the Triple Entente had taken shape. A naval arms race between Germany and Britain as well as diplomatic and military crises in Morocco, the Balkans, and elsewhere contributed to an uneasy peace.