Fort Jay was initially built in 1776 to protect New York City
from the British Navy, and although it was not completely successful, concerns
about the fort aided Washington's strategic retreat after the defeat
in the Battle of Brooklyn. The fort was named for John Jay, one of the country's founding fathers.
In the 1790s, the earthworks were rebuilt in anticipation of a war with France that
never materialized and the gatehouse may date from that time. From 1806 to 1809 the
earthworks were replaced with granite and brick walls and a dry moat designed by
Army Chief Engineer Jonathan Williams.
The fort's importance diminished with the construction of Fort
Hamilton and Fort Wadsworth in the Narrows and brick barracks were built to replace
wooden barracks inside the fort. During the Civil War the fort was ringed with
50 Rodman cannons and the barracks were used to temporarily house captured Confederate
officers. Although advances in artillery made the fort obsolete in
the early 20th century, the cannons survived until 1942 when all but three were
scrapped for the war effort.