Propaganda was used to get men to enlist, for people to buy bonds and for general support for the war. Propaganda techniques varied by country. Many methods included emasculating message to weaken a man virility, trying to shame into going. Many tried romance and adventure, approaches also patriotic duty and a direct appeal. I think all the different methods were very effective. Some poster played the family card with the wife and child trying to get the father to go to war, gilt them in to enlisting.
The Canadian war posters had a Britain feel to then due to Britain having political and military control over Canada. They often used the union jack, were published in English and French and the posters addressed specific audiences. The United States before entering the war in 1917, a poster was created by James Montgomery Flag to get men enlisted for war. The famous poster was Uncle Sam “I want YOU for the U.S. Army.” The French poster tended to aim towards higher level of aesthetic. Were often designed by art school students and used traditional allegorical imagery towards the end promised war would end to reassure the public.
German posters didn’t turn away from modern abstract style. Weren’t really able to convey emotion impact through abstraction. The poster didn’t set well with the majority of Germans. They felt they would have won the war if they had done better with propaganda.