If we deal with state Germanophobia, the first observation concerns the uniqueness of war in the sense that it means that the government became overtly rather than covertly xenophobic in order to create a level of support on the home front necessary for victory on the battlefield, especially before conscription was introduced at the beginning of 1916. In Britain during the First World War, the government established various agencies for the propagation of Germanophobia.
Source: wiktionary