Mancus

Mancus (sometimes spelt mancosus or similar) was a term used in early medieval Europe to denote either a gold coin, a weight of gold of 4.25g (equivalent to the Islamic dinar, and thus lighter than the Byzantine solidus), or a unit of account of thirty silver pence. This made it worth about a month's wages for a skilled worker, such as a craftsman or a soldier. Distinguishing between these uses can be extremely difficult: the will of the Anglo-Saxon king Eadred, who died in 955, illustrates the problem well with its request that "two thousand mancuses of gold be taken and minted into mancuses" (nime man twentig hund mancusa goldes and gemynetige to mancusan).

The origin of the word mancus has long been a cause of debate. One suggested interpretation linked it to the Latin adjective mancus, meaning 'defective', which was thought to be a reference to the poor quality of gold coinage circulating in eighth-century Italy. However, it has become clear that the earliest references to payments in mancuses, which occur in north-eastern Italy in the 770s, specifically refer to Islamic gold dinars. Consequently, a second theory has appeared: that mancus derives from the Arabic word منقوش manqūsh (from the triliteral verbal root n-q-sh 'to sculpt, engrave, inscribe'), which was often employed in a numismatic context to mean 'struck'.

After its first appearance in the 770s, use of the term mancus quickly spread across northern and central Italy, and leapfrogged over Gaul to reach England by the 780s. A letter written in 798 to King Coenwulf of the Mercians by Pope Leo III mentions a promise made in 786 by King Offa to send 365 mancuses to Rome every year. Use of the term mancus was at a peak between the ninth and eleventh centuries, and was only restricted to very specific locations and contexts thereafter.

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