I'm currently working on a novel called "The Few Who Led the Many." This is a story of a husband-and-wife team who are among the earliest practitioners of the art of public relations. They do so by staging events, manipulating images, and creating themes — such as "Eating eggs are good for your health" — then getting the American Medical Association to endorse this recommendation.
Their employer would be The American Farm Bureau Federation. Typically, their other clientele includes politicians, major corporations, and government.
The story starts immediately before World War I and ends with the John F. Kennedy assassination — certainly an eventful period in American history.