The so-called “solidus” was minted in Constantinople during the reign of Eastern Roman Emperor Theodosius II (401-450), likely around the year 440. It is a coin of 4.54 grams (0.16 oz) of pure gold, with the obverse featuring a portrait of the emperor and the reverse the female symbolizing Constantinople.
The site where the coin was found – at the edge of Budapest – was a major Roman outpost on the northern border of the empire. It started as a garrison of the 6,000-strong Adiutrix II legion and a city gradually developed around the fortress. At its height in the 2nd century AD the city had 30,000 to 40,000 inhabitants.
Archeologists speculate that the gold coin was probably part of a series of gifts and payments by Constantinople to the Huns, in exchange for peace. At the time, a solidus was worth 320 liters of grain or the equivalent of an equestrian soldier’s service payment for a month and a half.