Egypt · 196 BC
Room 4 · Ground floorImagine finding a cheat sheet that unlocks a lost secret code. That is what this dark grey stone is.
More than two thousand years ago in Egypt, the same message was carved on it three times, in three different kinds of writing. At the top are hieroglyphs, the picture writing of the pharaohs. In the middle is Demotic, the everyday handwriting of Egyptians. At the bottom is ancient Greek.
Here is the problem. For more than a thousand years, nobody in the whole world could read hieroglyphs. But scholars could still read Greek. So if you know what the Greek says, you can start to work out what the hieroglyphs say.
In 1799, French soldiers found the stone while rebuilding a fort near a town called Rosetta. A couple of years later, the British defeated the French in Egypt and took the stone. It has been in this museum since 1802.
Then a young Frenchman called Jean-François Champollion worked on it for years. In 1822 he finally cracked the code. The story goes that he ran into his brother's office, shouted "I've got it!", and fainted.
So whenever you see hieroglyphs anywhere in the world and someone can tell you what they mean, this stone is the reason.
The text is a priestly decree, issued at Memphis in 196 BC, honouring the young king Ptolemy the Fifth on the anniversary of his coronation. In return for his gifts to the temples, the priests granted him divine honours. It is essentially a political announcement, and copies were set up in temples across Egypt.
Its importance comes from the three scripts. Hieroglyphs were the sacred script, Demotic was the administrative script of daily life, and Greek was the language of the ruling Ptolemaic dynasty, descended from one of Alexander the Great's generals. One message, three audiences.
The slab is granodiorite and weighs around three quarters of a tonne. The top is broken away, so the hieroglyphic section is the most incomplete. Centuries after it was made, the stone was reused as building material, which is how French soldiers came across it at Rashid, known in Europe as Rosetta, in 1799 during Napoleon's Egyptian campaign.
After the French surrender in 1801, the stone passed to the British under the terms of the capitulation. It has been on display here almost continuously since 1802, and it is one of the most visited objects in the museum.
Decipherment took two decades. The English scholar Thomas Young made early progress with the Demotic text and with the ovals, called cartouches, that surround royal names. Jean-François Champollion made the breakthrough in 1822, realising that hieroglyphs were not purely symbolic but combined sound signs with meaning signs.
Today the stone is also part of a wider debate about museum collections acquired through conquest, and there have been public calls for its return to Egypt. Look at the painted lettering on its sides, and you will see that the story of how it came here is literally written on the object.