A coin formerly in use in the Papal States. It was orig- inally struck in base silver and later in copper, and it obtains its name from its brown color, the Italian for a bay or brown tint being bajo . But Cinagli states that the name is probably derived from Bayeux, a town of France (old name, Bajocae), where there was at one time a mint.
The Baiocco was the tenth part of the Paolo, and the one hundredth part of a Scudo, and it was subdivided into five Quattrini.
In 1712 Pope Clement XI issued a sil- ver coin of 80 Baiocci, and in 1796 Pius VI struck a 60 Baiocci piece at Bologna in copper. Among the obsidional pieces Mail- liet cites copper coins of two and one half and five Baiocci struck during the French occupation of Civita-Vecchia, 1796-1797 ; five, two and one half, and one half Baiocci for San-Severino, 1797 ; and five Baiocci for Tivoli in 1797. See Ducato.
The Baiocco is mentioned by Andrew Boorde, in his Introduction to Knowledge , 1547 (179), who says, " In bras they haue Kateryns and byokes and denares. "
Source: Frey's Dictionary (American Journal of Numismatics, Vol. 50, 1916)