Fort Casimir

Fort Casimir was a Dutch fort in the seventeenth-century colony of New Netherland. It was located on a no-longer existing barrier island at the end of Chestnut Street in what is now New Castle, Delaware.

The Dutch called the Delaware River the Zuyd Rivier, or South River, and considered the lands along it banks and those of its bay to be the southern flank of its colony of New Netherland. In 1638, the Delaware Valley began to be settled by Swedes, Finns, Dutch, and Walloons and became the colony of New Sweden, though this was not officially recognized by the Dutch Empire.

The fort changed hands several times.

Shortly after his arrival to take up his position as up as Director-General of New Netherland in 1647, Peter Stuyvesant, attempted to re-assert control of the region and its lucrative trade. In his initial attempt at control, he effected the construction of Fort Beversreede near the terminus of the Great Minquas Path, at the mouth of the Schuylkill. The location of earlier-built Fort Nassau on the east bank (now New Jersey) of the river, had proved disadvantageous since the richest fur-trapping area of the native Susquehannock and Lenape populations was inland to the west. In 1651, Stuyvesant had the fort dismantled and relocated to the western bank downstream from Fort Christina, the first and one of the larger Swedish settlements. He named it Fort Casimir. Fort Beversreede was abandoned and the Dutch presence was consolidated.

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