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.