Spy literature that had evolved particularly from invasion stories was a reaction to various challenges arising from the foundation and rise of imperial Germany, economic challenges from other European powers, immigrants, and the Boer War, which seemed to challenge either Britain’s position in the world or its security. This resulted in the gradual acceptance of the need for secret police and secret services as the view of the spy changed from an objectionable person to somebody who could be patriotic and heroic. Spy/invasion literature from its beginning had a concern with convincing readers to a certain political and military viewpoint. From mid-Victorian times up to World War I the overall message in the literature was that Britain was in a Darwinian struggle for survival. Thus, it needed to become more efficient, which included the British male population required at least to be military trained to protect Britain from a landing invasion force. Another message was that immigrants, especially Jews and Germans, were an internal threat as their loyalties lay elsewhere, with their co-religionists or country of origin, making them all an internal threat to Britain.