1⁄12 Ecu - Louis I

Louis I ruled Monaco under French protection following the Treaty of Péronne in 1641, which bound the Grimaldis tightly to the French crown — a dependency clearly reflected in his coinage, which mirrors the monetary reforms of Louis XIV almost exactly. The 1⁄12 écu denomination itself was a product of that 1640s French reform, designed to regularize fractional silver across the realm and its client states.

The KM#41.2 and 41.3 distinctions within this issue reflect minor die variations documented across the striking period rather than any change in monetary policy or issuing authority.