May 19, 1898, was the day US Congress passed the “Private Mailing Card Act,” allowing private publishers and printers to produce postcards. They had to be labeled “Private Mailing Cards” until 1901, then they became known as “souvenir cards.” On December 1901, the Postmaster General issued Post Office Order No. 1447 which allowed the words “Post Card” instead of the longer “Private Mailing Card” on the back of the postcards. Messages were not allowed on the address side of postcards. Because of the absence of message space on the address side of postcards, this Post Card Period is also known as the “Undivided Back Period.”
In 1907, a major change on the address side of postcards occurred. This change was prompted by the Universal Postal Congress, the legislative body of the Universal Postal Union. The convention decreed that postal cards produced by governments of member nations could have messages on the left half of the address side effective October 1, 1907. These changes to the backs of postcards ushered in the “Divided Back Period,” which spans from 1907 until 1915. The” Divided Back Period” is also known as the “Golden Age of Postcards.”
During early postcard history, German printers dominated the market in postcard printing. However, with the beginning of WWI, American printers supplied most of the postcards in the United States. American printers did not have the same technology as German printers, so the quality of available postcards fell, and people lost interest in collecting them, effectively ending the “Golden Age of Postcards.” Printers saved ink during this time by not printing to the edge of the card and leaving a white border around the image, giving the time period its name, the “White Border” period. The postcard also had a description of the image on the message side, which retained the divided back.
Beginning in the 1930’s, new printing processes allowed printers to produce postcards with high rag content, which gave them a look of being printed on linen, rather than paper. The most notable printer of this period was Curt Teich & Co., which printed its first linen card in 1931 and whose postcards became popular around the world. Teich’s process allowed for quicker production and brighter dyes to be used to color the images. Most postcards retained the white border, though some were printed to the edge of the card. The back remained divided and usually contained printed information about the image. The production of linen postcards eventually gave way to photochrom postcards, which first appeared in 1939. However, linen cards continued to be produced for over a decade after the advent of photochrom postcards.
Modern photochrom-style postcards first appeared in 1939 when the Union Oil Company began to carry them in their western service stations. Production of the postcards slowed during WWII due to supply shortages, but after the war, they dominated the postcard market. The photochrom postcards are in color, and their images closely resemble photographs. Today postcards are typically purchased as souvenirs and used in direct mail marketing.
Resource, Smithsonian Institution Archives/postcard/history.