The Universal Postal Union

As international communication became more widespread in the mid-19th Century, postal treaties were negotiated between various individual countries which resulted in a confusing and tangled web of rates, routes, and regulations. The cost to send a letter depended not just on what country it was going to, but also what ship it was carried aboard. Spearheaded by German Postmaster-General Heinrich von Stephan, the establishment of the General Postal Union (now the Universal Postal Union) in 1874 allowed for uniform flat rate postage for a letter to any other member country. The UPU predates the United Nations (which it would later become a part of) by over seven decades and was one of the first modern intergovernmental organizations. Since its founding the UPU has been based in Bern, Switzerland.

The creation of the UPU simplified of overseas postage rates, as can be seen on this cover to Italy (right) paying 11 times the standard 5c rate. The triple-rate cover to England (left) bears 15c United States postage and 3d postage for forwarding within the United Kingdom.