Fort Armstrong was a 19th-century United States military installation located on Rock Island in the Mississippi River, near the present-day Quad Cities of Illinois and Iowa. Here's a summary of key information: Purpose and Establishment: It was built after the War of 1812 as part of a chain of frontier defenses. Its purposes included: Establishing a U.S. military presence in the region. Controlling and monitoring Native American populations, particularly the Sauk. Protecting American settlers. to act as a U.S. Army base of operations. Location: It was situated on Rock Island, which is now the site of the Rock Island Arsenal. History: Construction began in 1816, and it was named after John Armstrong, the U.S. Secretary of War. The fort played a significant role during the Black Hawk War in 1832, serving as a military headquarters. Treaties ending the Black Hawk War were signed at Fort Armstrong. The fort was abandoned by the U.S. Army in 1836. Later it was used as an ordnanc...