 Knowlton's Rangers, named after its leader Colonel Thomas Knowlton, became the first organized elite force, a predecessor to modern special operations forces units such as the Army Rangers, Delta Force, and others.The "1776" on the United States Army Intelligence Service seal refers to the formation of Knowlton's Rangers.In January 1863, Major General Joseph Hooker established the Bureau of Military Information for the Union Army during the Civil War, headed by George H. Sharpe.