The American Civil War

Theoutbreak of the Civil War presented the United States Post Office with an unexpected problem: postage stamps held by Southern post offices represented an asset which could, in theory, have been sold to individuals in the North and thereby advance the Confederate effort. Postmaster General Montgomery Blair ordered the production of new postage stamps in June of 1861 to replace those in use at the time. After a six-day window during which the public could exchange their old stamps for new ones, postmasters were instructed to no longer recognize the validity of any United States postage stamp produced prior to 1861. Despite confusion and logistical challenges, by the end of 1861 Blair’s scheme had been fully implemented. This was the last time United States stamps were demonetized, and all stamps printed from 1861 to the present day are valid for postage.

Attempts to use old postage stamps after the start of the Civil War were flagged by the post office, as seen here (left). A new stamp was required before the letter could be mailed. As the war raged on, both the North (right) and South (center) created decorative envelopes extolling their cause.