Part 1: the denier tournois of Philip II Augustus, invading the angevin territories of Richard Lion Heart
Under the reign of King Philip II Augustus (1180-1223), the kingdom of France represented a mosaic of local mints. The lords (seigneurs ) struck feudal deniers of about 1 gram weight with a silver content varying from one region to the other, and from one year to the other. Merchants were well aware of these quality variations.
Also, the clergy possessed their mints and thus, a denier from Mans (the mansois) was worth two of those struck in Angers or Tours (respectively : the angevin and the tournois). As for the south, the denier toulousain (Toulouse) was exchanged for two deniers from Melgueil or four from Le Puy.
Coinage circulating in territories under King Richard the Lion Heart ( Oxford 1157-1199 Châlus) were deniers mansois and later, with his takeover of Normandy , the region shifted from the denier de Rouen ( city of Rouen—episodically the Normandy capital at that time) , to the denier Angevin.
Meanwhile, within King Philip's domains, his deniers were prevalent, these being the denier of Paris called deniers parisis, similar in quality to the mansois and containing approximately 50 % silver which caused a problem since Plantagenet angevins contained only 32 %. Philip's coins were quickly vanishing on the market.
To counter the problem and avoid the Parisians wrath were there devaluation of any sort, the king turned to the Abbey of Tours situated in Plantagent territory and whose tounois were already known. Holding title as lay Abbot of Saint Martin of Tours, the king ordered legends modified to read : Philippus Rex, thus creating competition for the angevin within the Plantagenet fold.
It is theorized, but not yet proven, this manoeuvre took place during King Richard 's incarceration in Austria.
Thus , the peaceful Abbey of Tours unwittingly became King Philip's Trojan Horse.
Finally liberated, King Richard wasted no time sacking the abbey; expulsing it's clergy.
In later years when his brother John ruled and lost territories to the kingdom under fief laws of " commise" (confiscation )-- John found himself left with only Aquitaine and Poitou -- King Philipe in turn lost no time decreeing "denier" laws throughout recuperated lands.
By 1204 royal warrants issued in Normandy, warned :
"Let it be known, henceforth , within the king's lands, non are authorised, neither money-changers or any person whomever, to take forbidden coinage abroad. Such must either be exchanged or turned over to the law".
This coinage was to be exchanged for "deniers tournois" and recycled into royal money. The French king pragmatically set aside reserves of "denier mansois" and English "esterlins" to serve when propitious. These were valued as double or quadruple Philip's "denier tournois ."