Railway Mail Service

The United States Postal Service's Railway Mail Service was a significant mail transportation service in the US during the time period from the mid-19th century until the mid-20th century. The RMS, or its successor the Postal Transportation Service (PTS), carried the vast majority of letters and packages mailed in the United States from the 1890s until the 1960s.

George B. Armstrong, manager of the Chicago Post Office, is generally credited with being the founder of the concept of en route mail sorting aboard trains which became the Railway Mail Service. Mail had been carried in locked pouches aboard trains prior to Armstrong's involvement with the system, but there had been no organized system of sorting mail en route, to have mail prepared for delivery when the mail pouches reached their destination city.

In response to Armstrong's request to experiment with the concept, the first railway post office (RPO) began operating on the Chicago and North Western Railway between Chicago and Clinton, Iowa, on August 28, 1864. The concept was quickly seen as successful, and was expanded to other railroads operating out of Chicago, including the Chicago, Burlington and Quincy, Chicago and Rock Island, Pennsylvania and the Erie.

By 1869 when the Railway Mail Service was officially inaugurated, the system had expanded to virtually all of the major railroads of the United States, and the country was divided into six operating divisions. A superintendent was over each division, all under the direction of George B. Armstrong, who had been summoned from Chicago to Washington, D.C. to become general superintendent of the postal railway service. Armstrong served only two years as general superintendent before resigning because of failing health. He died in Chicago on May 5, 1871, two days after his resignation.

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