What does this tell us about the Crusades?
The Crusaders' imitation of Islamic gold dinars is a testament to the high value and broad recognition of gold dinars. The Crusaders knew that minting a new currency could destabilize the economies of their newly conquered lands, and instead they opted to mint imitations of these dinars. While the calligraphy on Fatimid coins was of higher quality than their Crusader imitations, to the untrained eye it is extremely difficult to differentiate the two (see comparison below).
Later, Pope Innocent IV (1243-1254) outlawed Arabic inscriptions on crusader gold dinars. New crusader gold coins featured a Christian cross, but the inscriptions continued to feature Arabic calligraphy rather than Latin, as crusaders knew the economy of the Kingdom of Jerusalem depended on the recognition of their coins within the tradition of Islamic dinars.