The inscription on the One Ring in J.R.R. Tolkien’s Middle-earth is written in the Black Speech.
Sauron created the One Ring in the fires of Mount Doom during the Second Age. Its inscription consists of two lines from a longer verse describing the Rings of Power: “One Ring to rule them all, One Ring to find them.” The writing appears when the Ring is heated, revealing fiery letters that are invisible in ordinary conditions.
The Black Speech was created by Sauron for the servants of Mordor. Tolkien used it sparingly, which makes the Ring inscription especially prominent. Its language and imagery underline the Ring’s role as an instrument of domination rather than a neutral magical object.
The inscription is sometimes mistakenly called Elvish because it is shown in elegant lettering and because the Ring was part of the broader history of the Elves and the Rings of Power. The script is Tengwar, but script and language are different things: the Tengwar writing system records the Black Speech words in this inscription.