When we reflect that the Franks living under the Lex Salica must have thus sunk into a small minority, it becomes obvious that wider views must of necessity have entered into the minds of Charlemagne and his advisers, not only as regards land, but also as regards the currency.
The currency of the Lex Salica only a local one.
The currency of the Lex Salica, with its solidi of 40 denarii, was, as has been said, after all a local one. And outside the old Frankish boundary, in the Wisigothic region, as well as probably in Italy, the Roman currency or local modifications of it apparently more or less prevailed. Ecclesiastics, as we have seen, even Alcuin himself, still used the terms of Roman currency in writing on monetary matters to their friends outside the Empire.
The Roman drachma or argenteus of 72 w.g. the silver denarius of the Empire.
To them the denarius was still the Roman drachma of 72 wheat-grains of silver, commonly called the argenteus, in contrast to the gold solidus or aureus.
Gregory of Tours, when he has occasion to mention monetary payments, speaks of aurei, trientes, and argentei. In one story he speaks of solidi, trientes, and argentei.[131]
Further, in a supplement to the laws of the Wisigoths[132] is a statement under the name of Wamba Rex (A.D. 672-680), which apparently represents the monetary system in vogue south of the Frankish boundary. It states that the pound of gold equalled 72 gold solidi, so that the gold solidus was not the Merovingian solidus but that of Constantine. It then states that the ‘dragma’ of gold = ‘XII argentei.’ The argenteus being the silver drachma, the ratio of gold to silver was 1:12.
To Isidore of Seville, from his Spanish standpoint, the silver drachma was still the denarius.[133]
Dragma octava pars unciæ est et denarii pondus argenti, tribus constans scripulis.