Across the Brazos by the great American artist Robert McGinnis (born 1926). McGinnis did over 1200 paperback book covers and movie posters. Here is a good example how the newly invented CinemaScope format also influenced the formats of paintings.
History painting dates back to the Renaissance and was long considered to be the "grand genre". Nevertheless it has its peak in the 19th century forged by Neoclassicism and Romanticism. There it became the artistic contribution in the process of the construction of National Identities of the European and American nations.
At the same time history painting under the influence of historism pretended to be "realistic", to show history how it has been. Above all it was this pretension that led to the great failure of History painting AND Realism at the end of the century.
When artists and their public realized that telling history always will be subjective and a painting will always be an illusion Realism and history painting lost their ground to modern painting.