The decipherment of Egyptian hieroglyphs was gradually achieved during the early 19th century. The most helpful clue was supplied by the discovery in 1799 of the Rosetta Stone, an inscription in three scripts. Building on work by several other scholars, notably Thomas Young, the breakthrough to decipherment was made by Jean-François Champollion.
The successful decipherment was preceded by a long period during which hieroglyphs were wrongly believed in Europe to be a purely ideographic script. In the 5th century appeared the Hieroglyphica of Horapollo, a spurious explanation of almost 200 glyphs. Authoritative yet largely false, the work was a lasting impediment to the decipherment of Egyptian writing. But whereas earlier scholarship emphasized Greek origin of the document, more recent work has recognized remnants of genuine knowledge, and casts it as an attempt by an Egyptian intellectual to rescue an unrecoverable past. The Hieroglyphica was a major influence on Renaissance symbolism, particularly the emblem book of Andrea Alciato, and including the Hypnerotomachia Poliphili of Francesco Colonna.
Later attempts at deciphering Egyptian hieroglyphs were made by Arab historians in medieval Egypt during the 9th and 10th centuries. By then, hieroglyphs had long been forgotten in Egypt, and were replaced by the Coptic and Arabic alphabets. Dhul-Nun al-Misri and Ibn Wahshiyya were the first historians to be able to at least partly decipher what was written in the ancient Egyptian hieroglyphs, by relating them to the contemporary Coptic language used by Coptic priests in their time. Arabic manuscripts of Ibn Wahshiyya's work were later read by Athanasius Kircher in the 17th century, and then translated and published in English by Joseph Hammer in 1806 as Ancient Alphabets and Hieroglyphic Characters Explained; with an Account of the Egyptian Priests, their Classes, Initiation, and Sacrifices in the Arabic Language by Ahmad Bin Abubekr Bin Wahishih, contributing to the complete decipherment of hieroglyphs.