That liberty shall not perish from the earth – buy liberty bonds: fourth liberty loan

Joseph Pennell; United States.; Alco-Gravure 1918 Lithograph

During World War I, the governments of belligerent countries issued bonds as a way to borrow money from its citizens in order to finance the war effort. The United States called these bonds Liberty Bonds. The bonds were issued four times during the war and a fifth time as a Victory Bond in 1919. Subscribing to the bonds became a symbol of patriotic duty. The government put on a massive sales campaign including posters, celebrity endorsements, air shows, stickers, and buttons to pressure the public into purchasing the bonds. Although individuals purchased war bonds valued between $5 and $100, half of the total sum was sold to financial institutions. The campaigns were quite successful raising $17 billion for the war effort. 

Fourth Liberty Loan poster