The Rosetta Stone was a key to discovering Egyptian because it provided a bilingual (Greek and Demotic Egyptian) and trilingual (Greek, Demotic Egyptian, and hieroglyphic Egyptian) text. This allowed scholars to decipher the hieroglyphic script, which had been lost since the 4th century AD. Champollion, a French linguist, was the first to decipher the Rosetta Stone and thus open the door to understanding ancient Egypt.