Venetian ducat

The ducat /ˈdʌkət/ was a gold or silver coin used as a trade coin in Europe from the later middle ages until as late as the 20th century. Many types of ducats had various metallic content and purchasing power throughout the period. The gold ducat of Venice gained wide international acceptance, like the medieval Byzantine hyperpyron and the Florentine florin, or the modern British Pound sterling and the United States dollar.

The word ducat is from Medieval Latin ducalis = "relating to a duke (or dukedom)", and initially meant "duke's coin" or a "duchy's coin".

The first issue of scyphate billon coins modelled on Byzantine trachea was made by King Roger II of Sicily as part of the Assizes of Ariano (1140). It was to be a valid issue for the whole kingdom. The first issue bears the figure of Christ and the Latin inscription Sit tibi, Christe, datus, quem tu regis iste ducatus (meaning "O Christ, let this duchy, which you rule, be dedicated to you") on the obverse. On the reverse, Roger II is depicted in the style of a Byzantine emperor and his eldest son, Duke Roger III of Apulia, is depicted in battle dress. The coin took its common name from the Duchy of Apulia, which the younger Roger had been given by his father.

Doge Enrico Dandolo of Venice introduced a silver ducat which was related to the ducats of Roger II. Later gold ducats of Venice, however, became so important that the name ducat was associated exclusively with them and the silver coins came to be called grossi.

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