Which ancient writing system was deciphered after the discovery of the Rosetta Stone?

Egyptian hieroglyphs were deciphered after the discovery of the Rosetta Stone.

The Rosetta Stone is a granodiorite decree created in 196 BCE during the reign of Ptolemy V. The same text appears in three scripts: Egyptian hieroglyphs, Demotic, and Ancient Greek. Because scholars could already read Greek, the parallel versions provided a crucial key for understanding the Egyptian scripts.

French soldiers discovered the stone near the town of Rashid, called Rosetta by Europeans, in 1799. Thomas Young made important advances, including identifying royal names, while Jean-François Champollion published a major decipherment of hieroglyphic writing in 1822. Hieroglyphs were not simply pictures: they could represent sounds, words, or semantic categories. The stone is often said to have “translated” the script by itself, but it was the combination of repeated names, grammatical analysis, and comparison with Coptic that made the breakthrough possible. The British Museum has held the stone since 1802, after its transfer under the Treaty of Alexandria.