Infantry timelines · Infantry numbers 1–200

2d Infantry Regiment

A century of division assignments

1916–2026 · Regimental service, battle groups, battalions and deployments.

2d Infantry Regiment unit graphic
2d Infantry Regiment
First division shown19th Division (World War I)27 Jul 1918
Separate battalion histories2 documented elementsDated lineages and service notes below
Page cutoff8 September 2026Last-documented status is explicitly marked

One regiment, separate assignments

The common row follows the regiment. After its reorganization, battle groups and battalions could hold different assignments at the same time. A deployment or temporary attachment does not by itself change the assigned division. The common row closes on 1 Jun 1957; later service belongs to the separate element rows. Battalion rows follow headquarters lineages, often descended from lettered companies, rather than assuming that the old regimental battalions continued unchanged.

Division patches

6th Infantry Division5th Infantry Division1st Infantry Division24th Infantry Division9th Infantry Division10th Mountain Division

Representative division patches. Patterns could change over time; an image does not imply that the exact version was worn throughout every period. Divisions without a verified asset remain identified by name.

The dated record

Division timeline

Battalion overview →

Deployments, operations and credited campaign service appear inside assignment cards. Award years establish credited service, not exact tour dates. Some service notes identify only company-sized elements. This is a sourced selection, not a complete movement log.

Assignment ends are exclusive: the next period starts on that date. *Striped final bars mean last documented, with later status unverified through the page cutoff. Unknown intervals are not treated as inactive.

  1. 1 Jan 1916 – 27 Jul 1918

    2d Infantry Regiment

    Assignment not established

    The available record does not establish a precise assignment throughout this interval. No division is inferred.

    Source

  2. 27 Jul 1918 – 14 Feb 1919

    2d Infantry Regiment

    19th Division (World War I)

    Division names are normalized across historical redesignations. This entry follows the cited unit lineage.

    Source

  3. 14 Feb 1919 – 24 Mar 1923

    2d Infantry Regiment

    No assigned division

    The cited record establishes service outside an assigned division. Higher headquarters and temporary operational attachments could still direct the unit.

    Source

  4. 24 Mar 1923 – 16 Oct 1939

    2d Infantry Regiment

    6th Infantry Division

    Division names are normalized across historical redesignations. This entry follows the cited unit lineage.

    Source

  5. 16 Oct 1939 – 20 Sep 1946

    2d Infantry Regiment

    5th Infantry Division

    Division names are normalized across historical redesignations. This entry follows the cited unit lineage.

    Source

    Deployments & overseas operations

    1. 1944-1945

      Normandy, Northern France, Rhineland, Ardennes-Alsace and Central Europe

      2d Infantry Regiment · Campaign service

      Campaign participation is recorded in the Army lineage. The year label summarizes campaign service, not an exact overseas tour.

      Source
  6. 20 Sep 1946 – 15 Jul 1947

    2d Infantry Regiment

    Inactive

    The unit or its headquarters lineage was inactive. This status does not imply that every inherited honor or divisional affiliation was erased.

    Source

  7. 15 Jul 1947 – 30 Apr 1950

    2d Infantry Regiment

    5th Infantry Division

    Division names are normalized across historical redesignations. This entry follows the cited unit lineage.

    Source

  8. 30 Apr 1950 – 1 Mar 1951

    2d Infantry Regiment

    Inactive

    The unit or its headquarters lineage was inactive. This status does not imply that every inherited honor or divisional affiliation was erased.

    Source

  9. 1 Mar 1951 – 1 Sep 1953

    2d Infantry Regiment

    5th Infantry Division

    Division names are normalized across historical redesignations. This entry follows the cited unit lineage.

    Source

  10. 1 Sep 1953 – 25 May 1954

    2d Infantry Regiment

    Inactive

    The unit or its headquarters lineage was inactive. This status does not imply that every inherited honor or divisional affiliation was erased.

    Source

  11. 25 May 1954 – 1 Jun 1957

    2d Infantry Regiment

    5th Infantry Division

    Division names are normalized across historical redesignations. This entry follows the cited unit lineage.

    Source

  12. 1 Jun 1957 – 19 Feb 1962

    1st Battle Group / Battalion lineage

    Inactive

    The unit or its headquarters lineage was inactive. This status does not imply that every inherited honor or divisional affiliation was erased.

    Source

  13. 19 Feb 1962 – 12 Jul 1965

    1st Battle Group / Battalion lineage

    5th Infantry Division

    Division names are normalized across historical redesignations. This entry follows the cited unit lineage.

    Source

  14. 12 Jul 1965 – 1 Oct 1983

    1st Battle Group / Battalion lineage

    1st Infantry Division

    Division names are normalized across historical redesignations. This entry follows the cited unit lineage.

    Source

    Deployments & overseas operations

    1. 1965-1970

      Vietnam

      1st Battle Group / Battalion lineage · Credited overseas service

      The Army lineage lists a unit decoration for service in these years. These are credited service years, not exact deployment and return dates. More than one assignment falls in the opening year; this year-level service marker does not establish the assignment on a particular deployment day.

      Source
  15. 1 Oct 1983 – 16 Mar 2008

    1st Battle Group / Battalion lineage

    Inactive

    The unit or its headquarters lineage was inactive. This status does not imply that every inherited honor or divisional affiliation was erased.

    Source

  16. 16 Mar 2008 – 1 May 2013

    1st Battle Group / Battalion lineage

    172d Infantry Brigade · Separate

    This headquarters is not a division. Temporary attachments in the service entries below are distinct from the formal assignment.

    Source

    Deployments & overseas operations

    1. 2008-2009

      Iraq

      1st Battle Group / Battalion lineage · Credited overseas service

      The Army lineage lists a unit decoration for service in these years. These are credited service years, not exact deployment and return dates.

      Source
  17. 1 May 2013 – 1 Jun 2013

    1st Battle Group / Battalion lineage

    Assignment not established

    The parent brigade inactivated during this month. A precise effective date for this battalion is not established here.

    Source

  18. 1 Jun 2013 – page cutoff*

    1st Battle Group / Battalion lineage

    Last documented: Inactive

    The unit or its headquarters lineage was inactive. This status does not imply that every inherited honor or divisional affiliation was erased. The source establishes this last recorded status, not uninterrupted service through 2026. The striped bar extends to the page cutoff to keep the later research gap visible.

    Source

  19. 15 Feb 1957 – 28 Jan 1959

    2d Battle Group / Battalion lineage

    1st Infantry Division

    Division names are normalized across historical redesignations. This entry follows the cited unit lineage.

    Source

  20. 28 Jan 1959 – 19 Feb 1962

    2d Battle Group / Battalion lineage

    24th Infantry Division

    Division names are normalized across historical redesignations. This entry follows the cited unit lineage.

    Source

  21. 19 Feb 1962 – 12 Jul 1965

    2d Battle Group / Battalion lineage

    5th Infantry Division

    Division names are normalized across historical redesignations. This entry follows the cited unit lineage.

    Source

  22. 12 Jul 1965 – 15 Apr 1970

    2d Battle Group / Battalion lineage

    1st Infantry Division

    Division names are normalized across historical redesignations. This entry follows the cited unit lineage.

    Source

    Deployments & overseas operations

    1. 1965-1969

      Vietnam

      2d Battle Group / Battalion lineage · Credited overseas service

      The Army lineage lists a unit decoration for service in these years. These are credited service years, not exact deployment and return dates. More than one assignment falls in the opening year; this year-level service marker does not establish the assignment on a particular deployment day.

      Source
  23. 15 Apr 1970 – 21 Mar 1973

    2d Battle Group / Battalion lineage

    Inactive

    The unit or its headquarters lineage was inactive. This status does not imply that every inherited honor or divisional affiliation was erased.

    Source

  24. 21 Mar 1973 – 15 May 1991

    2d Battle Group / Battalion lineage

    9th Infantry Division

    Division names are normalized across historical redesignations. This entry follows the cited unit lineage.

    Source

  25. 15 May 1991 – 16 Feb 1996

    2d Battle Group / Battalion lineage

    Inactive

    The unit or its headquarters lineage was inactive. This status does not imply that every inherited honor or divisional affiliation was erased.

    Source

  26. 16 Feb 1996 – 16 Apr 2007

    2d Battle Group / Battalion lineage

    1st Infantry Division

    Division names are normalized across historical redesignations. This entry follows the cited unit lineage.

    Source

    Deployments & overseas operations

    1. 2004

      An Najaf and Fallujah, Iraq

      2d Battle Group / Battalion lineage · Credited overseas service

      The Army lineage lists a unit decoration for service in these years. These are credited service years, not exact deployment and return dates.

      Source
  27. 16 Apr 2007 – 15 Jul 2014

    2d Battle Group / Battalion lineage

    1st Infantry Division

    Division names are normalized across historical redesignations. This entry follows the cited unit lineage.

    Source

    Deployments & overseas operations

    1. 2011-2012

      Afghanistan

      2d Battle Group / Battalion lineage · Credited overseas service

      The Army lineage lists a unit decoration for service in these years. These are credited service years, not exact deployment and return dates.

      Source

    2. 2013-2014

      Afghanistan

      2d Battle Group / Battalion lineage · Credited overseas service

      The Army lineage lists a unit decoration for service in these years. These are credited service years, not exact deployment and return dates. The labeled service overlaps an assignment change and is listed only once; consult the following assignment cards as well.

      Source
  28. 15 Jul 2014 – 16 Sep 2014

    2d Battle Group / Battalion lineage

    No assigned division

    The cited record establishes service outside an assigned division. Higher headquarters and temporary operational attachments could still direct the unit.

    Source

  29. 16 Sep 2014 – 16 Sep 2015

    2d Battle Group / Battalion lineage

    Inactive

    The unit or its headquarters lineage was inactive. This status does not imply that every inherited honor or divisional affiliation was erased.

    Source

  30. 16 Sep 2015 – page cutoff*

    2d Battle Group / Battalion lineage

    Last documented: 10th Mountain Division

    Division names are normalized across historical redesignations. This entry follows the cited unit lineage. The source establishes this last recorded status, not uninterrupted service through 2026. The striped bar extends to the page cutoff to keep the later research gap visible.

    Source

    Deployments & overseas operations

    1. 2017-2018

      Iraq

      2d Battle Group / Battalion lineage · Credited overseas service

      The Army lineage lists a unit decoration for service in these years. These are credited service years, not exact deployment and return dates.

      Source

Sources and scope

Army Center of Military History lineage certificates provide the dated backbone. Regimental associations and secondary histories supplement individual operations and battalions. Where the evidence stops, the page says so. A page cutoff is not a claim that every unit directory was current on that date.

Earlier battalions are covered by common regimental service; separately dated lineages and substantiated later battalions receive their own rows or notes. A unit graphic alone is not evidence of a battalion assignment. Reserve, training and inactive organizations are distinguished from active combat units.

  1. U.S. Army Center of Military History: 2d Infantry Regiment
  2. U.S. Army Center of Military History: 1st Battalion 2d Infantry Regiment
  3. U.S. Army Center of Military History: 2d Battalion 2d Infantry Regiment
  4. NCO Journal: 172nd Infantry Brigade cases its colors, May 2013

Patch artwork

Unmodified artwork from Wikimedia Commons; individual file pages identify the artist and license. Insignia represent the divisions, not regimental affiliation badges.