Second United States Army Second United States Army was originally formed 15 October 1918 during World War I . It functioned as a training and administrative headquarters until being deactivated 15 April 1919 . It operated 1933 to 1966 , training and organizing troops for overseas deployment during World War II . It later operated under U . S . Army Forces Command as a regional command to control Army Reserve forces 1983 to 1995 . Second Army was reactivated on 1 October 2010 as U . S . Army Cyber Command / Second Army , it is based at Fort Belvoir , Virginia . History . World War I . Second Army ' s task during the First World War was to hold the line a short distance east of the Moselle River in France following the end of the Saint - Mihiel offensive along the Western Front . The army was also tasked with reinforcing units from the active - in - combat soldiers of the U . S . First Army . On 10 November , Second Army advanced on German positions , already in disorder and retreating . Word did not reach the units advancing until after eleven - hundred hours on 11 November , making it one of the last units to fight to the very conclusion of the war . On 15 April 1919 , Second Army was deactivated . World War II . Second United States Army was reactivated on 1 October 1933 under a plan developed by then - Army Chief of Staff Douglas MacArthur to consolidate forces in the continental United States under four regional army commands . It was headquartered in Memphis , Tennessee . In 1940 , with the activation of Army General Headquarters ( succeeded by Army Ground Forces in 1942 ) , the four field armies were given responsibility for training forces in their respective areas and conducting maneuvers to evaluate training and readiness . In September 1941 , Second U . S . Army participated in large - scale maneuvers pitting it against Third U . S . Army in what were known as the Louisiana Maneuvers . Over 350 , 000 troops took part . Also in 1941 , four regional defense commands were established coterminous with the army areas , and the Commander , Second U . S . Army became also Commanding General , Central Defense Command . With First and Fourth Armies be given primary responsibility for defense of the eastern and western coasts of the United States , and later with First Army ' s relocation to England to command U . S . Army forces in the invasion of France , Second and Third Armies assumed increasing responsibility for the training and organization of the rapidly expanding army and preparing troops for overseas deployment . When Third Army headquarters was relocated to France in 1944 to serve as a combat command , Second Army assumed its stateside responsibilities as well . Second U . S . Army was commanded from 1940 to 1943 by Lt . Gen . Ben Lear . He was succeeded by Lt . Gen . Lloyd Fredendall after Fredendall ' s removal from command in North Africa . General Fredendall held command until war ' s end . Post - World War II . In November 1964 , as an effort to reorganize military operations , the Department of the Army announced the closure of Fort Jay at Governors Island New York and the relocation of U . S . First Army to Fort Meade , Maryland . First and Second Armies would merge and Second Army subsequently inactivated . It had been proposed that First Army be inactivated , but its commander Lt . General Robert W . Porter , Jr . strongly protested the proposal and it was dropped . In the end , Second Army headquarters staff were retained and became the new staff for U . S . First Army . On 1 January 1966 at Fort Meade , Second Army was deactivated and its colors cased by commander , Lt . General William F . Train who then assumed command of U . S . First Army . Second Army was reactivated on 1 October 1983 under U . S . Army Forces Command as a regional command to control Army Reserve forces in the southeastern United States , including Puerto Rico and the U . S . Virgin Islands . It was headquartered at Fort Gillem , Georgia . It was again deactivated on 3 July 1995 with First Army once again assuming its functions . First Army was then relocated to Fort Gillem . Current . On 1 October 2010 , Second Army was again re - activated as United States Army Cyber Command ( ARCYBER ) / Second Army . The new command is based out of Fort Belvoir , Virginia and a part of the larger , U . S . Cyber Command ( CYBERCOM ) . Lieutenant General Rhett A . Hernandez became the first commander of the newly reactivated Army .