This French four sols coin, dating to the reign of Louis XIV, was one of many coins found at the mouth of the Bagaduce River in 1840. The number and diversity of coins indicated the area's thriving and complex trade system in the 1600s. One side of the coin was stamped a man's profile and the text "LVDOVICV3.XIIII.D.G.RA." The reverse side depicted an elaborate diamond with a "D" in the center, and the words "RANET.NAVARRAE.REX."

Present day Castine was a contested area of overlapping Wabanaki, English and French claims for centuries. In 1674, during a period of French control, Dutch privateers attacked the fort and took the Baron of Saint-Castin (Jean Vincent d’Abbadie) and others hostage for ransom. When Saint-Castin returned to Castine in 1677, he established a trading post among Wabanakis on the Bagaduce River, about six miles from the old fort.

In 1684 Chief Madockawando’s daughter, Pidianiske (baptized as Molly Mathilde), married Saint-Castin and solidified the alliance between the French and Penobscot. Family ties and reciprocal relations gave Saint-Castin a stronger footing among Wabanaki people than the English settlers and traders encroaching up the coast.