Infantry timelines · Infantry numbers 1–200

109th Infantry Regiment

A century of division assignments

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

109th Infantry Regiment unit graphic
109th Infantry Regiment
First division shown28th Infantry Division11 Oct 1917
Separate unit histories3 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 1959; 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.

Approximate wartime windows identify documented affiliations within the labeled years. Their boundaries are coverage limits, not assignment or inactivation orders. Unverified intervals remain visible; common regimental service does not establish the later assignments of each battalion.

Division patches

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 – 11 Oct 1917

    109th Infantry Regiment

    Assignment not established

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

    Source

  2. 11 Oct 1917 – 1 Jan 1919

    109th Infantry Regiment

    28th Infantry Division

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

    Source

    Deployments & overseas operations

    1. 1918

      France · World War I

      109th Infantry Regiment · Deployment / campaign service

      Includes combat or depot/replacement service as described in the regimental history; not every regiment fought as an intact formation.

      Source
  3. 1 Jan 1919 – 1 Apr 1921

    109th Infantry Regiment

    Assignment not established

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

    Source

  4. 1 Apr 1921 – 22 Oct 1945

    109th Infantry Regiment

    28th Infantry Division

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

    Source

    Deployments & overseas operations

    1. 1944-1945

      European theater · World War II

      109th Infantry Regiment · Deployment / campaign service

      Selected campaign service; year labels do not specify exact departure and return dates. The labeled service overlaps an assignment change and is listed only once; consult the following assignment cards as well.

      Source
  5. 22 Oct 1945 – 16 Dec 1946

    109th 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

  6. 16 Dec 1946 – 1 Jun 1959

    109th Infantry Regiment

    28th Infantry Division

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

    Source

  7. 1 Jun 1959 – 1 Sep 2007

    1st Battle Group / Battalion lineage

    28th Infantry Division

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

    Source

  8. 1 Sep 2007 – page cutoff*

    1st Battle Group / Battalion lineage

    Last documented: 28th Infantry 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. 2012-2013

      Kuwait

      1st Battle Group / Battalion lineage · Deployment / campaign service

      Selected campaign service; year labels do not specify exact departure and return dates.

      Source
  9. 1 Apr 1963 – 1 Mar 1992

    2d Battle Group / Battalion lineage

    28th Infantry Division

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

    Source

  10. 1 Mar 1992 – page cutoff*

    2d Battle Group / Battalion lineage

    Last documented: Converted to another branch

    Lineage service in another branch or under a predecessor designation. This interval is not plotted as an infantry maneuver-division assignment. 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

  11. 24 Mar 1964 – 17 Feb 1968

    3d 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

  12. 17 Feb 1968 – 1 Apr 1975

    3d 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. 1 Apr 1975 – 1 Oct 1995

    3d Battle Group / Battalion lineage

    28th Infantry Division

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

    Source

  14. 1 Oct 1995 – page cutoff*

    3d Battle Group / Battalion lineage

    Last documented: Converted to another branch

    Lineage service in another branch or under a predecessor designation. This interval is not plotted as an infantry maneuver-division assignment. 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

Sources and scope

Army Center of Military History lineage certificates, regimental associations and secondary histories document assignments, operations and battalions. Exact lineage dates and approximate historical coverage are distinguished. 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. 109th Infantry Regiment history (Wikipedia; secondary)

Patch artwork

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