Prince Frederik's Battery

by Charles Consolvo

No records have been located documenting any activities at the Battery after 1815.  There is a Hamburg America Line postcard from about 1900, showing the battery with cannons mounted, sent by an unknown passenger on the SS Blucher in 1907.

Prince Frederik’s Battery ( re-named Ft. Willoughby by the British during their occupation 1807-1815) is located on the southeastern tip of Hassel Island, guarding the entrance to the harbor of St. Thomas. Shown is a section of a map of the harbor from 1780 with the Battery located by the arrow. 

Research in the Danish Archives, funded under a grant from the National Park Service, revealed that planning for construction of the Battery began in 1767, when it was proposed that a Battery of six 8lb cannons be constructed at what was then called Magens Point, when revenues were available, although if war commenced, it was to be immediately constructed. Ft. Christian, (C) on the map, could not stop vessels from entering the harbor. The objective was to keep privateers from entering and seizing merchant ships.  In 1776 an English ship sailed into Frederiksted harbor on St. Croix, causing great consternation.  Construction of the Battery commenced in 1777 and by 1780 it was completed. During this period, a total of 5,265.44 Danish rigsdalers was expended on construction. The next mention of the Battery comes in 1782, when a boat was purchased to service the Battery, together with a lock and chain. In 1786 an inquiry was made as to the best way to secure the cannons so they are not carried away by the sea. Apparently very violent waves had been causing a problem. The agreed solution was to install iron staples in the floor and wall of the cannon platform and to chain the cannons.  This was accomplished, and two of the staples (ring bolts) can still be found on the platform today.  During this entire period, a large number of barrels of lime were used, probably for whitewashing the walls of the Battery.  It was recorded that the battery saved an English merchant ship from a privateer, and in gratitude, the ship captain provided the Battery with some gunpowder. Lt. Peter Oxholm, a Danish officer sent out from Denmark to survey and make a report on the fortifications of the Danish West Indies produced the map, above, and also a drawing of the completed Battery, which provides identification of its structures.

The structure to the left on the drawing is the latrine and kitchen, the one on the right includes the quarters for soldiers, a powder magazine and a cistern.  The terreplein (a flat space where a battery of guns is mounted) shows six cannons, and at the western end (center bottom of plan) a set of stairs “leading to a battery not yet constructed”, which remains true today! 

 

The Battery’s only recorded battle, and the basis for the National Park Service American Battlefield Protection Program grant received by the Trust, occurred on March 3, 1801.  Rumors of war with England had reached Danish Governor von Scholten on St. Croix, together with news of Danish ships being seized by the English.  On the morning of March 3, 1801, von Scholten dispatched the Danish brig of war HDMS Lougen under the command of Captain Jessing together with the war schooner Den Aarvagne to cruise to St. Thomas to gain intelligence of the rumored war.  In the event of obtaining such intelligence, the Den Aarvagne was to immediately carry the news to St. Croix.  Nearing the western end of the island of St. Thomas, the two Danish ships encountered two English ships, the sloop of war, HMS Arab, and the privateer Experiment.  The Arab apparently fired several shots near the Lougen to warn her to heave to.  The Lougen apparently responded with a broadside, and a running battle took place, beginning about 4 in the afternoon, heading east along the southern shore of St. Thomas.   Eventually, the Lougen drew sufficiently close to the Battery for it to join in the battle, and the Arab ceased its pursuit, unwilling to suffer damage from the Battery.   The accounts of the battle in Danish records and English records differ significantly. 

Despite this heroic effort by the Danes, on March 28, an English fleet of 29 ships together with approximately 4,000 men appeared off St. Thomas and the island was surrendered without a shot being fired.  The English occupied St. Thomas for about a year, returning the island to Denmark in 1802.  They again seized St. Thomas in 1807, renaming the Battery as Fort Willoughby, and remained until 1815 when the island was again returned to Denmark under the Treaty of Vienna, ending the Napoleonic Wars.

With funds from the grant from the National Park Service, the Trust has acquired an extremely detailed 3 dimensional baseline laser survey of the Battery, together with an underwater survey of the surrounding area which located several cannonballs undoubtedly associated with the Battery, and a detailed list of recommendations for stabilization of the Battery.  In addition, the consultant for the project is producing a virtual 3 dimensional model of the Battery as it appeared in 1780.  Shown below is an initial model of the Battery.