On August 24th, 1912, the U.S. Congress approved a law providing parcel post service and authorized the preparation and production of stamps to pay the parcel fees, effective January 1, 1913. Prior to 1912 private companies delivered parcels throughout the United States. This was a lucrative business, especially in rural areas. The Post Office Department realized parcel post service would be a great source of revenue, and the government intervened accordingly.
Alan Berkun