Posters can inspire and motivate; that's why so many office walls are still covered with them. In 1935 Franklin Delano Roosevelt founded the Works Progress Administration (WPA) to create jobs during the depression; 5300 artists were put to work at the Federal Art Project, known to Republicans as "one more link in the vast and unparalleled New Deal propaganda network." We have shown a lot of motivational posters from the World Wars before, but Core77 points to a vast trove at the Library of Congress that were produced before WWII promoting tourism, health, safety and other issues that are stunning and inspiring still.
Earlier poster posts:
"Make do and mend"- Posters from World War 1 can inspire today
See All Our Posters from the Past That Have Lessons for the Present