Denier - Louis I Strasbourg mint, City gate

Louis I — "the Pious" — inherited the Frankish empire intact from Charlemagne in 814 and immediately set about reforming its administration, including tightening control over the royal mints. Strasbourg, as a major Rhine crossing point and trading hub, was among the active imperial mints in this early period of his reign. The 814–818 bracket places this denier before Louis's monetary reforms of 818–819, which standardized output more aggressively across the empire and reasserted royal monopoly over coinage that had begun drifting toward episcopal and comital control.

Prou's reference number 43 groups this type among the earliest Ludovician issues, structurally continuous with late Carolingian practice under Charlemagne rather than representing a clean break.