1 Cavallo - Louis I

Louis I ruled Monaco under French protection following the treaties of 1641, which ended a century of Spanish suzerainty over the principality. The cavallo — a denomination inherited from Italian monetary tradition — was the smallest circulating unit, produced in billon precisely because the metal shortage affecting much of southern France and northern Italy made pure copper issues impractical for a mint of Monaco's limited output. Twenty years is a long production window for a coin this small; survivors in any condition are genuinely scarce, as heavy circulation and billon's susceptibility to corrosion conspired against them.