The Rosetta Stone

Pierre-François Bouchard, was an officer in the French Army of engineers serving under Napoleon. He is most famous for discovering the Rosetta Stone in Egypt in 1799.
The Rosetta Stone is inscribed with three versions of a decree issued in Egypt in 196 BC on behalf of King Ptolemy V Epiphanes. The first two sections of text are written in Ancient Egyptian using hieroglyphic and Demotic scripts respectively. But the bottom is written in ancient Greek. Because there are only very minor differences among the three versions, the Rosetta Stone essentially became a decryption key to understanding Egyptian hieroglyphic writings – making a deeper understanding of Egyptian history possible.