Modern studies have shown that Charlemagne and Louis the Pious had strong control over the Frankish coinage. This gave them both political and economic advantages. Between 792/793 and 840, trade expanded and the Carolingian Empire became increasingly monetised, although the use of coins still varied from region to region.
On Christmas Day 800, Pope Leo III crowned Charlemagne as Roman Emperor. After this coronation, imperial and Christian imagery became increasingly important in Carolingian coinage. The temple or church type with a Christian legend was introduced under Charlemagne in the early 9th century and was later struck in much larger numbers under his son, Louis the Pious.
Under Louis the Pious, the 'Christiana religio' deniers were produced in large quantities. These coins usually do not mention a mint name. The reverse shows a stylised temple or church façade, surrounded by the legend XPISTIANA RELIGIO.
These coins were struck across the Carolingian Empire, including regions broadly corresponding to modern France, the Rhineland, northern Italy and the Low Countries. There are many varieties and differences in style. In some cases, details such as style, die links and hoard evidence can help attribute a coin to a specific mint.
Half-deniers, also known as obols, were also minted, but on a much smaller scale. These obols are therefore considerably rarer than the deniers.
