There was no envelope, just the sheet
Before envelopes appeared, a letter and its outer covering were the same sheet. It was folded in a special way, sometimes cut and threaded with a strip cut from the same sheet, then covered with wax. The result was a packet that could not be opened without damaging it.
Write and fold. The text ended up inside, with the blank side outside: that was where the address was written.
Fasten it. A strip of paper or a thread was threaded through the cuts, pulling the packet tight.
Apply the wax. A drop covered the fastening point and hardened within seconds.
Make the impression. A personal mark was pressed into the wax with a signet ring or seal matrix. Reproducing it without the same ring was impossible.
Folding methods varied in how secure they were, and historians are still analyzing them, sometimes quite literally: they have learned to read surviving unopened letters with a tomograph, without unfolding them and destroying the structure itself.
A wax seal protected a letter from prying eyes.
It did not protect against reading, but against reading without leaving a trace. Anyone could open a letter, but no one could restore it to its original state with the impression intact.
A seal instead of a signature
The impression had a second job too: it confirmed who the sender was. In a society where few people could write or compare handwriting, a personal mark in wax served as identification. A signet ring was something people did not put into other hands and often destroyed after its owner's death.
That is where its legal force came from. A document was considered valid if it bore the seal of the right person or institution. Forging a seal was a separate and serious crime, far more serious than forging a signature.
Color and material spoke too. Red wax was considered ordinary, black was used in mourning, and special colors were assigned to institutions. The recipient understood something about the letter before opening it.
All this disappeared fairly quickly. With the arrival of mass-produced envelopes and adhesive flaps, the point of the complicated construction vanished, and identification shifted to the signature and letterhead. The seal remained as decoration and a ceremonial mark.
Why could opening a sealed letter not be hidden?
What second role did a seal on a letter have?
Sources
- The ways letters were folded and sealed are studied as a separate area of material culture history
- in 2021, unopened 17th-century letters were read using X-ray tomography without opening them
Next in the “Letters and Diaries” series
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