On August 28, 1864, while the nation was still in the midst of the Civil War, the Post Office Department established the Railway Mail Service. The new service revolutionized the way mail was processed by sorting mail aboard moving trains, not just in post offices. Trains had been carrying mail for almost 30 years by that time. Under that system, mail bags were loaded onto the trains to be carried to another post office for processing. Some were delivered, but many others were put back into bags for another train trip. Some postal officials began wondering if they could improve that process by putting clerks on the trains to sort mail along the way, dramatically reducing the time it took to receive a letter.
