Lucasfilm artist Amy Beth Christenson, who has worked as a concept artist on
Star Wars: The Clone Wars,
Star Wars: Rebels, as well as several LucasArts games, including
The Force Unleashed, explains the work that went into the recently revealed propaganda-style posters for
Star Wars: Rebels. Based on designs from the 1940's, the posters are meant to convey pro-Imperial propaganda, with an empahasis on recruitment, keeping the local systems from rebelling, and the Imperial forces portrayed heroically. Sketches were narrowed down
to the final six designs, cleaned up, colored, and given a layer of graininess. Christensen also adds, even with the simplified designs, most of what you see on the posters is taken directly from the final show designs, and a preview of what's to come.
(Source:
The Official Star Wars Blog)