1 Ecu - Louise Marguerite

Château-Regnault was a tiny principality in the Ardennes held by Louise Marguerite de Lorraine, Princess of Conti, who acquired it through her marriage to François de Bourbon-Conti. The right to strike coin was a jealously guarded privilege, and for a domain this small to exercise it in 1617 — during the regency turbulence following Henri IV's assassination — signals deliberate political assertion rather than economic necessity. The issue is extremely rare in any condition, surviving primarily in cabinet collections assembled by 19th-century French regional numismatists.