Successively redeveloped, the fort was used first by Bermudian Militia and then by regular Royal Artillery units from 1612 into the 20th century.

[1] It was one of a number of forts built immediately following the Virginia Company being given official sanction in 1612 for its possession of Bermuda, which it had occupied since the wreck of the Sea Venture in 1609.

While most of these forts were designed to prevent an enemy entering St. George's Harbour, either directly from the open Atlantic, or via Castle Harbour, Fort St. Catherine's, was placed in a location to prevent vessels which had entered through the reefline from the open Atlantic via the main shipping channel from rounding St. George's Island and moving to Westward.

Vessels passing this way are constrained by the surrounding reeflines, and must travel near to shore, and cannot take evasive manoeuvres, making the site a very useful one for coastal artillery.

Today, the fort houses a museum dedicated to Bermudian history, particularly the military aspect.