A Brief History Of Traditional Wedding Envelopes.
Did you ever wonder why wedding invitations are enclosed in two envelopes? This is a tradition that dates back to soon after the Industrial Revolution (ca. 1800) and the invention of lithography. Lithography is a printing process in which chemicals are used to accept and print ink, instead of the labor- and time-intensive processes of calligraphy (elegant handwriting) or engraving (carving) which had been two popular methods before. Lithography was a cheap printing technique that allowed wedding invitation producers to market their products to the then-burgeoning middle class. Delivery of these newly-minted invitations would prove to be problematic, however, as the postal service of the time was still unreliable. Thus, two envelopes were used: an inner one, unsealed (for the sake of courtesy), and an outer one, addressed and used to protect the inner from the rigors of travel.
Elizabeth Post, in her etiquette book Emily Post On Weddings (1994, Harper-Collins, New York), elaborates:
The use of two envelopes is a tradition that probably goes back to when invitations where delivered by hand. For politeness the envelopes were left unsealed. Later, when mail services, began, the unsealed envelopes were inserted into larger ones that could be sealed. A practical reason for using two envelopes today is that the names of family members, escorts of your invited guests and children can be listed on the inner envelope.
Since the modern U.S. Postal Service requires a return address on all first-class or better mail, the “sanctity” of the inner envelope (and thus, the invitation) can be preserved by the outer one. You can affix stamps to and print the mailing and return addresses on the outer envelope, and avoid marring the more personal inner envelope.
As you can see, the tradition of the double wedding envelope is in place for both practical and aesthetic reasons. Double envelopes add class and flair to your wedding ensemble.