If artists contributed to the British war effort, so did writers. In fact, in the twenty or so years leading up to the First World War, growing concerns over Germany's war-like intentions created an atmosphere of anxiety.
Novels such as The Battle of Dorking and The Riddle of the Sands led people to expect a German invasion, or at least to mistrust the Kaiser.
This pre-war poster is advertizing a play being staged at Wyndham's Theatre in London, entitled, "An Englishman's Home". The title refers to the popular saying, "An Englishman's home is his castle", which attempts to promulgate the notion that the ownership of property was inviolate in England, that the homeowner's status was well protected by law, and woe betide anyone who tried to interfere with his privileges.
Here we see Britannia, the spirit of Britain. She was a figure familiar to British people of the time through her appearance on the penny coin. She seems to be warning a gent peaceably enjoying his hearth that the enemy are at the gates.
My latest novel - The Deadly Playground, 1914 might also be of interest to you. Click here to take a look.