"The term "parcel post" refers to the sending of packages through the mail service. In 1878, the Congress of the Universal Postal Union established an international parcel post system. Four years later, the British parliament approved a bill implementing domestic, colonial and foreign parcel post services. Other countries quickly followed suit. The US Post Office Department agreed to deliver parcels sent into the country but refused to institute a domestic service.
"In the late 1800's, the National Grange and similar organizations concerned with farmers' welfare lobbied Congress for the free delivery of mail to rural households. Many rural residents had to travel for days to retrieve their mail from distant post offices or pay private express companies for delivery. Finally, in October 1896, Congress approved the establishment of rural free delivery. It was a heady taste of life for rural Americans and soon increased the demand for delivery of packages containing foodstuffs, dry goods, drugs, tobacco and other commodities not easily available to farmers.
"Private express companies and rural retail merchants fought tenaciously against parcel post but rural residents comprised 54 percent of the country's population and they were equally vociferous. While the question was still being debated in Congress, one of the major express companies declared a large stockholder dividend. Public indignation at the exorbitant profits spurred Congress to resolve the issue quickly" (http://www.sil.si.edu/ondisplay/parcelpost/intro.htm, accessed 11-07-2013).