377th Theater Sustainment Command

The 12th Port of Embarkation, later designated 377th Theater Sustainment Command, was constituted on 2 July 1942 and was activated 5 July 1942 at Fort Dix, New Jersey. The unit was converted, reorganized, and redesignated 7 November 1942 as the 12th Port. The unit was inactivated 4 January 1946 at Camp Kilmer, New Jersey and later redesignated 3 November 1948 in New Orleans, Louisiana, as the 377th Transportation Major Port. On 11 September 1950 the 377th was called to Camp Kilmer, New Jersey. Later, the unit moved to Fort Eustis, Virginia and stayed on active Federal Service until 10 October 1952. From 1953 until 1963, the 377th remained in a Reserve status and experienced several changes in unit designation.

On 31 December 1965, the unit was re-designated as the 377th Support Brigade under the Army Logistical Concept. On 16 October 1979, it was renamed the 377th Corps Support Command. It retained the designation until 16 July 1981 when it was designated as a Theater Army Area Command (TAACOM). On 1 October 1998 the TAACOM wartime mission expanded and the unit designation was changed to the 377th Theater Support Command.

The TSC serves as a Force Support Package unit with an ongoing support mission in its area of operation. Over 500 downtrace units throughout the United States, Puerto Rico, Guam and the Virgin Islands provide support to the TSC for training and wartime mission guidance. Whether at home station, deployed across the country or overseas, the TSC trains to achieve its peacetime and wartime mission of providing command and control of assigned units to ensure and maintain a high state of readiness. The TSC prepares wartime-aligned units to accomplish their mission by developing, executing and evaluating training. The TSC provides daily logistics support to its wartime higher headquarters for missions and exercises.

Subordinate units
As of 2022 the following units are subordinated to the 377th Theater Sustainment Command:
 * 4 Sus Cmd SSI.jpg 4th Sustainment Command (Expeditionary), in San Antonio, Texas
 * 90th Sustainment Brigade, in Little Rock, Arkansas
 * 211th Regional Support Group
 * 300th Sustainment Brigade, in Grand Prairie, Texas
 * 77th Quartermaster Group (Petroleum)


 * 143SustCmdExpedSSI.svg 143rd Sustainment Command (Expeditionary), in Orlando, Florida
 * 321st Sustainment Brigade, in Baton Rouge, Louisiana
 * 518th Sustainment Brigade, in Knightdale, North Carolina
 * 207th Regional Support Group, in Fort Jackson, South Carolina
 * 641st Regional Support Group, in St. Petersburg, Florida
 * 642nd Regional Support Group, in Decatur, Georgia
 * 310 Sus Cmd SSI.jpg 310th Sustainment Command (Expeditionary), in Indianapolis, Indiana
 * 55th Sustainment Brigade, in Fort Belvoir, Virginia
 * 38th Regional Support Group, in Charleston, West Virginia
 * 643rd Regional Support Group, in Whitehall, Ohio
 * 354th Quartermaster Group in Whitehall, Ohio
 * 316 Sus Cmd SSI.jpg316th Sustainment Command (Expeditionary), in Coraopolis, Pennsylvania
 * 77th Sustainment Brigade, in Joint Base McGuire-Dix-Lakehurst, New Jersey
 * 301st Regional Support Group, in Butler, Pennsylvania
 * 475th Quartermaster Group, in Farrell, Pennsylvania
 * 655th Regional Support Group, in Chicopee, Massachusetts
 * 3rd Transportation Brigade (Expeditionary), in Fort Belvoir, Virginia
 * 2-REVISED-ARMY RESERVE SUSTAINMENT CMD-ssi.jpgArmy Reserve Sustainment Command, in Birmingham, Alabama
 * Deployment Support Command, in Birmingham, Alabama
 * 1179th Transportation Brigade, in Fort Hamilton, New York
 * 1173rd Transportation Battalion, in Brockton, Massachusetts
 * 1174th Transportation Battalion, in Fort Totten, New York
 * 1185th Transportation Battalion, in Lancaster, Pennsylvania
 * 1398th Transportation Battalion, in Baltimore, Maryland
 * 1189th Transportation Brigade, in North Charleston, South Carolina
 * 1182nd Transportation Battalion, in North Charleston, South Carolina
 * 1186th Transportation Battalion, in Jacksonville, Florida
 * 1188th Transportation Battalion, in Decatur, Georgia
 * 1190th Transportation Brigade, in Baton Rouge, Louisiana
 * 1181st Transportation Battalion, in Meridian, Mississippi
 * 1184th Transportation Battalion, in Mobile, Alabama
 * 1192nd Transportation Battalion, in New Orleans, Louisiana
 * 1394th Transportation Brigade, in Camp Pendleton, California
 * 1395th Transportation Battalion, in Joint Base Lewis–McChord, Washington
 * 1397th Transportation Battalion, in Vallejo, California
 * 757th Transportation Battalion (Railway Operations), in Milwaukee, Wisconsin