According to the Postal History Foundation, this envelope was postmarked in Tucson, Arizona Territory, March 23, 1867.

Jack Mount, an avid collector of postcards and postmarks, purchased an envelope postmarked in Tucson, Arizona Territory in 1867.

It is the oldest postmarked envelope known to exist from the area.

Mount bought it to donate it to the Postal History Foundation. According to the foundation, the envelope was postmarked March 23, 1867, and sent to Providence, Rhode Island.

Tucson’s post office was first established in 1857 when Tucson was part of New Mexico Territory.

The Civil War resulted in the discontinuance of the southern U.S. mail route for a time.

The Arizona Territory was established in 1863 and the Tucson Post Office was reestablished after the Civil War.

It received its first Arizona Territory canceling device on July 13, 1865.

Mount volunteers at the Postal History Foundation once a week and knew the envelope was an important piece of history.

“It belongs in a museum, where everybody can have access to it,” he said.

It is not currently on display but may be seen by appointment at the Postal History Foundation, located at 920 N. 1st Ave.

Other exhibits are available 8 a.m.-3 p.m. weekdays. For more information, go to postalhistoryfoundation.org or call 520-623-6652.

Contact Johanna Eubank at jeubank@tucson.com