The famous race between Seabiscuit and War Admiral takes place in the 1930s during the Great Depression. War Admiral was purchased by Sam Riddle, a wealthy businessman from the east coast, while Seabiscuit was owned by Charles Howard, who was well off, but nowhere near Riddle's millionaire status, and he lived in California.
So what you have was the upstart underdog horse in Seabiscuit, who represented the poor, down and out citizen during the Depression, as well as those out west (who often felt disrespected by the east) while War Admiral represented the wealthy elite from the east coast, the favorite, the advantaged and pampered, who every average man in America wanted to beat. Rich vs. Poor, West vs. East. Part of what makes the race and the rivalry such a great story is how representative it was of everything happening in American society in that troubled time.