The first fort established at the site was called Fort Alabama and was built by troops led by Colonel William Lindsay in March 1836. The fort came under attack by a large force hostile Indians almost immediately and was abandoned in April 1836. It was later completely destroyed by a booby-trapped keg of gunpowder.
At the end of 1836, orders were issued to reestablish Fort Alabama as a strong picket work with blockhouses at opposing angles. The post was located at a strategic point along the Fort King to Fort Brooke trail at a bridge crossing of the Hillsborough River. A force of 430 soldiers left Fort Brooke on November 30, 1836, to reestablish the fort under the command of Lieutenant Colonel William S. Foster. Their orders were to rebuild the fort and the bridge that had been destroyed months earlier. By December 19th, he had erected two blockhouses, a large storehouse, and the fort. By the end of the year, the bridge and powder magazine were completed. Upon inspection, Brevet Major General Thomas S. Jesup declared the work satisfactory and named the new post Fort Foster.
The fort’s primary purpose was to defend the bridge crossing the Hillsborough River and act as a resupply point for the soldiers in the field. On January 1, 1837, Colonel Foster boasted in a letter to General R. Jones that, “the works at Fort Foster on the Hillsborough River …. Fort & Bridge form one of the best and strongest field fortifications ever erected against Indians.”
The armament and supplies at Fort Foster were well stocked, including a six-pounder gun and a howitzer with at least 100 rounds of ammunition for each, 40 thousand rounds of rifle powder and bullets, 50 thousand ball and buckshot cartridges. There were also 50 thousand rations of subsistence and 10,000 bushels of corn. Tools of every description that might be required for service in the field were also stocked at the fort.
The fort was garrisoned on and off from December 1836, thru April 1838. From January 1836, thru March 1837, the fort was garrisoned predominately by sailors. U.S. Navy Lieutenant Thomas J. Lieb, 50 sailors, and 20 artillery soldiers were assigned to defend the fort and bridge.
The fort came under Indian attack and was plagued by sickness and disease. General Jesup lobbied Washington to allow the Indians to remain in south Florida and to close the unhealthy posts but he was rebuked by Washington and replaced by General Zachary Taylor.
The worst attack of the fort came in February 1836, when Seminole warriors attempted to set fire to the bridge, but the Indians were thwarted by aggressive musket and cannon fire from the sailors and the artillerymen. Seminole attacks increased to a point that forced Lieutenant Lieb to send a message to Fort Brooke for reinforcements. In response, 150 Marines were dispatched to Fort Foster to assist the sailors. When the Marines arrived, the Seminole rethought their intentions and fled. That summer, the fort was abandoned because of disease among its forces.
General Taylor ordered the post abandoned in May 1838 but it was reoccupied in December 1841. It was closed again at the end of the Second Seminole War in 1842. It was reopened in 1849 for short periods to meet the needs of the military when Seminole activity threatened.
When the Third Seminole War began in 1855, the post was reoccupied, at which time, it was referred to as “Old fort Foster.” A supply depot was opened for the third war one-half mile north of the Fort. When the war was over it was abandoned for the final time and deteriorated.
The fort site was added to the National Register of Historic Places in June 1972 and a replica of the fort was constructed at the site by the state and opened in February 1980. It is owned and operated by the Florida State Park system as Fort Foster State Historic Site as part of Hillsborough River State Park. Access to the fort is controlled by park rangers and limited to guided tours on specific days. The Fort Foster State Historic Site is located at 15402 U.S. 301 N. in Thonotosassa, Florida.
Compiled by Kathy Weiser-Alexander, updated October 2018