The general plan of this film is strongly reminiscent of two films that Walt Disney made at the request of the State Department during World War II, namely SALUDOS AMIGOS and THE THREE CABALLEROS. The content here is serious and dramatic, the Disney approach is funny entertainment in cartoon form, but similarities are unmistakable.
It is also my understanding that the U.S. State Department sent Orson Welles to Brazil to make a film. Reels and Reels of film were shot, the funding fathers were not given progress reports that convinced them that anything like they wanted would ever result, and the funding was cut off. The fate of the reels and reels of Welles shot film seems quite similar to what happened to Que Viva Mexico.
As a personal evaluation and comment, I would like to add to what others have written, that I saw nothing in this film that could possibly be construed as blatant propaganda. Great films like CASABLANCA and GONE WITH THE WIND have a strong propaganda element to them, the first one, wartime "Us are Good Guys, Nazis are Bad" and the second one "Slavery and the Ku Klux Klan were the good guys, Dixie and the Old South were just wonderful". QUE VIVA Mexico has less propaganda.