In the world of the ancient Mediterranean, there were plenty of ways for the upper class to flaunt their wealth. Just like today, the elites lived in massive houses, wore luxurious clothing, and dined on decadent delicacies. But for the 1 percent of the 1 percent, there was a status symbol shrouded in myth and worth more than gold: purple.

Dyes were difficult to produce in the ancient world. All dyes were made from a natural source like a plant, animal, or mineral, and some were rarer than others. One of the rarest, though, was Tyrian purple.

Tyrian purple was made from the secretions of a certain sea snail, called a Murex. It took thousands of these snails to produce even a small amount of usable dye, making Tyrian purple extremely expensive. It was worth the cost, however; Tyrian purple was famous because over time its color would not fade but actually become brighter and more beautiful.

Tyrian purple was named after the Phoenician city of Tyre, where the dye was first produced in the Bronze Age. The Phoenicians exported purple all around the Mediterranean, making their dye and themselves quite popular. Some historians even speculate that the word "Phoenician" is derived from the Greek word for "purple."

The dye took the Mediterranean world by storm. In the Iliad and the Odyssey, Homer reserves purple for the greatest warriors and kings. King Solomon supposedly decorated the Temple of Jerusalem with Tyrian purple. Alexander the Great and his successors wore purple as their symbol of royal authority. The Mediterranean was also awash with myths about how human beings first discovered purple.

Tyrian purple would earn its other name, imperial purple, from the Romans. In the Roman Republic, the high-ranking magistrates wore the toga praetexta, a white toga with a purple stripe. Generals celebrating a triumph, a festival that was the highest honor a general could receive, were allowed to wear the solid purple toga picta.

After the Republic became the Empire, purple was increasingly associated with the emperor and his subordinates. According to Roman historians, the emperor Caligula once sentenced a Roman client-king to death for the arrogance of wearing purple.

In the coming centuries, the Roman government would even nationalize the production of purple, and save the dye for the emperor. In the reign of Diocletian in the late third and early fourth centuries, one pound of purple wool was worth a pound of gold, and one pound of purple dye was worth three pounds of gold.

In the Eastern Roman Empire, purple was the property of the emperor. To become emperor was to be "raised to the purple" and to be the child of an emperor was to be "born in the purple." Purple was used for the most important imperial documents, and a splash of purple on one's clothes marked one as a bishop or imperial administrator.

Even after the fall of the Western Roman Empire, purple remained popular. The westerners could still purchase purple from the easterners, who produced it in Constantinople. Charlemagne was wearing purple when he was crowned the Holy Roman Emperor in 800, and was wearing purple when he was buried. The nobility and the clergy used purple to represent their secular and sacred power.

After the Ottomans conquered Constantinople in 1453, the production of purple went into decline. Western Europe could no longer purchase purple, and the nobility and clergy were forced to start using scarlet instead.

However, purple's association with might and majesty never quite disappeared. For centuries it remained the color of royalty, and many churches use purple vestments as symbols of authority. The ceremonial robes used in academia, modeled after clerical vestments, are often purple to represent intellectual excellence.

In America, the Purple Heart, along with its predecessor the Badge of Military Merit, uses purple to represent valor. Artificial dyes have made purple available to everyone nowadays, but it has never lost its association with greatness.