For nearly 1400 years, no one knew how to read Egyptian hieroglyphs. Virtually all understanding of this mysterious script had been lost since the 4th century AD.
 
The breakthrough  came in 1799, a year after Napoleon's armies successfully captured the Egyptian Nile Delta.Credit is given to a French soldier, while working at a fort on the Rosetta branch of the Nile River,he found a black basalt stone slab carved with inscriptions that would change the course of Egyptology.

The Rosetta Stone (now in the British Museum) was carved with an inscription in three different scripts: Egyptian hieroglyphs at the top, demotic script (a late cursive form of hieroglyphs) in the middle, and Greek at the bottom. The translation of the Greek passage revealed that the inscription was a royal edict issued on March 27, 196 BC. The decree recorded the benefits conferred on Egypt by the 13-year-old pharaoh Ptolemy V Epiphanes at the time of his coronation. The Greek inscription was a translation of the upper two Egyptian passages and thus provided the key to deciphering ancient hieroglyphs.

Copies of the Rosetta Stone inscription were sent to linguistic experts in Europe. The final breakthrough was made by the Frenchman Jean-François Champollion , who published his results in 1822.