1794-1890: Served primarily as a military installation.
Revolutionary War Period: After British occupation of New York, the U.S. Government constructed coastal fortifications in the harbor.
Federal Acquisition: The Federal government purchased Ellis Island from New York State in 1808.
Fort Gibson: In the early 19th century amid tensions with Britain, Fort Gibson was constructed on Ellis Island between 1811 and 1813 as part of New York Harbor’s defensive network, designed to protect the port from naval attack during the War of 1812. Facilities included gun batteries, barracks, and powder magazines. Over decades, as technology and military needs changed, the fortification use gradually diminished. By the late 19th century, military operations phased out, paving the way for new functions. Ellis Island uniquely combined military, immigration, and public health roles into the 20th century.