In October of 1808, Dearborn ordered a company of soldiers to occupy the fort and instructed them to do whatever was necessary to enforce the Embargo Act against embargo-breaking ships. The embargo was finally lifted in March of 1809.
In addition, various units manned Fort Preble during the War of 1812. Among them were elements of the Regiment of Light Artillery, the 21st, 33rd, and 34th Regiments of Infantry, as well as U.S. Volunteers — and in times of crisis local militia. When Winfield Scott and other American soldiers returned from British imprisonment in Quebec, they were landed at Fort Preble. Many of them were emaciated and ill, and some died at this post's hospital.
The fort remained manned through the Civil War, World War I and World War II. It was decommissioned in 1950. Spring Point Ledge Light was built near the site in 1897.
Wish I could take credit for this photo, but I just couldn't jump that high. This photo was borrowed from Wikipedia.