List of United States military and volunteer units in the Mexican–American War

This is a list of United States military units that participated in the Mexican–American War.

Regiments of dragoons

 * 1st Regiment of Dragoons, Colonel Richard B. Mason
 * 2nd Regiment of Dragoons, Colonel William S. Harney
 * 3rd Regiment of Dragoons, Colonel Edward G. W. Butler, (appointed from Louisiana)

Mounted riflemen

 * Regiment of Mounted Riflemen, Colonel Persifor F. Smith

Regiments of artillery

 * 1st Regiment of Artillery, Lt. Colonel Benjamin K. Pierce
 * 2nd Regiment of Artillery, Colonel James Bankhead
 * 3rd Regiment of Artillery, Colonel William Gates
 * 4th Regiment of Artillery, Lt. Colonel Matthew M. Payne

Regiments of infantry

 * 1st Regiment of Infantry, Colonel William Davenport
 * 2nd Regiment of Infantry, Lt. Colonel Bennet Riley
 * 3rd Regiment of Infantry, Lt. Colonel Ethan A. Hitchcock
 * 4th Regiment of Infantry, Lt. Colonel John Garland
 * 5th Regiment of Infantry, Lt. Colonel James S. Mcintosh
 * 6th Regiment of Infantry, Colonels: Zachary Taylor; Newman S. Clarke
 * 7th Regiment of Infantry, Lt. Colonel Joseph Plympton
 * 8th Regiment of Infantry, Colonel William J. Worth

Regiments of infantry, 1847

 * These units were raised according to an act of Congress, February 11, 1847 for an enlistment period of one year.


 * 9th Regiment of Infantry, Colonel Truman B. Ransom, (appointed from Vermont)
 * 10th Regiment of Infantry, Colonel Robert E. Temple, (appointed from New York)
 * 11th Regiment of Infantry, Colonel Albert C. Ramsey, (appointed from Pennsylvania)
 * 12th Regiment of Infantry, Colonel Milledge L. Bonham, (appointed from South Carolina)
 * 13th Regiment of Infantry, Colonel Robert M. Echols, (appointed from Georgia)
 * 14th Regiment of Infantry, Colonel William Trousdale, (appointed from Tennessee)
 * 15th Regiment of Infantry, Colonel George W. Morgan, (appointed from Ohio)
 * 16th Regiment of Infantry, Colonel John W. Tibbatts, (appointed from Kentucky)
 * Regiment of Voltigeurs and Foot Riflemen, Colonel Timothy P. Andrews, (appointed from District of Columbia)

Alabama

 * Battalion of Alabama Volunteers, for 3 months (4 companies); May–August 1846. Lt. Colonel Phillip H. Raiford
 * Battalion of Alabama Volunteers, for during the war with Mexico (5 companies); November and December 1847 – June 1848. Major John I. Seibels
 * 3 Independent Companies of Alabama Volunteers, for 6 months; received for 3 months, May–August 1846:
 * 1st Independent Company of Alabama Volunteers, for 6 months; Captain Robert Desha
 * 2nd Independent Company of Alabama Volunteers, for 6 months; Captain William H. Platt
 * 3rd Independent Company of Alabama Volunteers, for 6 months; Captain Rush Elmore
 * Independent Company of Alabama Mounted Volunteers, for during the war with Mexico; June 1847 – July 1848. Captain James McGee

Arkansas

 * Regiment of Arkansas Mounted Volunteers, for 12 months; June 1846 – June 1847. Colonels: Archibald Yell (killed at Buena Vista); John S. Roane (Lt. Colonel to February 28, 1847)
 * Independent Companies of Arkansas Mounted Volunteers in the Mexican War:
 * 1st Independent Company, Arkansas Mounted Volunteers; May 27, 1847 – June 24, 1848. Captain Gaston Meares (late Lt. Colonel Arkansas Volunteer Regiment)
 * 2nd Independent Company, Arkansas Mounted Volunteers; June 15, 1847 – June 1848. Captain Stephen B. Euyart; Served in New Mexico, and on the Rio Grande

California

 * Battalions of California Volunteers, for 3 and for 6 months; recruited in July and October 1846 – April 1847. Lt. Colonel Commanding John C. Freemont (Bvt. Captain Topographic Engineers and Major of Volunteers, July 23 and October 26, 1846 – April 19, 1847)
 * Mounted Rifle Company A. Captain Richard Owens
 * Mounted Rifle Company B. Captain Henry S. Ford
 * Mounted Rifle Company C. Captain Granville P. Swift
 * Mounted Rifle Company D. Captain John Sears
 * Mounted Rifle Company E. Captain John Grigsby
 * Mounted Rifle Company F. Captain Lansford W. Hastings
 * Mounted Rifle Company G. Captain B. K. Thompson
 * Mounted Rifle Company H. Captain Richard T. Jacobs (Spy Company chiefly of native Indians)
 * Artillery Company A. Captain John K. Wilson (Midshipman U.S. Navy)
 * Artillery Company. Captain William Findlay
 * Mounted Rifle Company. Captain Samuel Gibson (wounded at San Pasqual)
 * Company of Native Californians. Captain Santiago E. Arguello

Florida

 * 1st Independent Company of Florida Volunteers, for 12 months; February 1847 – March 1848. Captain William W. J. Kelly; Served at Guadaloupe and Santa Fe, Mexico
 * 2nd Independent Company of Florida Volunteers, for during the Mexican War; August 1847 – July 1848. Captains: K. G. Livingston, (died February 9, 1848 at Guadaloupe, Mexico); George Holmes (2nd Lieutenant to March 1848)

Georgia

 * Regiment of Georgia Volunteers, for 12 months; June 1846 – May 1847. Colonel Henry R. Jackson
 * Battalion of Georgia Volunteers, for during the war with Mexico, (5 companies); July 1847 – July 1848. Lt. Colonel Isaac G. Seymour
 * Battalion of Georgia Mounted Volunteers, for during the war with Mexico, (6 companies); September 1847 – July 1848. Lt. Colonel James S. Calhoun (late Capt. in Jackson's Regt.)
 * Independent Company of Georgia Mounted Men; May 1847 – August 1848. Captain John Loyall

Illinois

 * 1st Regiment of Illinois Volunteers, for 12 months; June 1846 – June 1847. Colonels: John J. Hardin (Killed at BuenaVista); William Weatherford (Lt. Colonel to February 26, 1847)
 * 2nd Regiment of Illinois Volunteers, for 12 months; June 1846 – June 1847. Colonel William H. Bissell
 * 3rd Regiment of Illinois Volunteers, for 12 months; July 1846 – May 1847. Colonel Ferris Foreman
 * 4th Regiment of Illinois Volunteers, for 12 months; July 1846 – May 1847. Colonel Edward D. Baker
 * lst Regiment of Illinois Volunteers, for during the war with Mexico; June 1847 – October 1848. Colonel Edward W. B. Newby
 * 2nd Regiment of Illinois Volunteers, for during the war with Mexico; August 1847 – July 1848. Colonel James Collins
 * Independent Companies of Illinois Mounted Volunteers, for the war with Mexico:
 * 1st Company Illinois Mounted Volunteers; May 21, 1847 – November 7, 1848. Captain Adams Dunlap (served with Brigadier General Wool)
 * 2nd Company Illinois Mounted Volunteers; August 1847 – July 26, 1848. Captain Wyatt B. Stapp
 * 3rd Company Illinois Mounted Volunteers; August 13, 1847 – October 26, 1848. Captain Michael K. Lawler (served with Brigadier General Wool)
 * 4th Company Illinois Mounted Volunteers; September 13, 1847 – July 25, 1848. Captain Josiah Littell

Indiana

 * 1st Regiment of Indiana Volunteers, for 12 months; June 1846 – June 1847. Colonel James P. Drake
 * 2nd Regiment of Indiana Volunteers, for 12 months; June 1846 – June 1847. Colonels: Joseph Lane (appointed Brigadier General U.S. Volunteers, July 1, 1846); William A. Bowles
 * 3rd Regiment of Indiana Volunteers, for 12 months; June 1846 – June 1847. Colonel James H. Lane
 * 4th Regiment of Indiana Volunteers, for during the war with Mexico; June 1847 – July 1848. Colonel Willis A. Gorman (late Major of J. H. Lane's Regt.)
 * 5th Regiment of Indiana Volunteers, for during the war with Mexico; October 1847 – July 1848. Colonel James H. Lane (late Colonel 3rd Regiment Indiana 12 months Volunteers)

Iowa

 * Battalion of Iowa "Mormon" Volunteers, for 12 months, (5 companies); recruited and mustered at Council Bluffs, Indian Territory on July 16, 1846 and discharged July 16, 1847 at Los Angeles; Lt. Colonels: James Allen (Captain 1st U.S. Dragoons, died at Fort Leavenworth August 23, 1846); acting commander Jefferson Hunt (senior Captain, Co A, Mormon Battalion, from August 23 to August 29, 1846); Andrew Jackson Smith (1st Lieutenant 1st Dragoons, acting August 30, 1846 to October 12, 1846); Philip St. George Cooke (Captain 1st Dragoons, October 13, 1846 – May 13, 1847 when he relinquished command of the Battalion to accompany Gen. Stephen W. Kearny back to Ft. Leavenworth); acting commander Jefferson Hunt (senior Captain, Co A, Mormon Battalion, from May 13 to July 16, 1847).

The Mormon Battalion was recruited as a federal volunteer unit, not through the state of Iowa which was not created until December 1846. The Mormon Battalion was raised at the express invitation of President James K. Polk, not as part of any state or territorial requisition for troops.

The contemporary official Army documents refer to the unit in the following ways; Prior to Allen recruiting the unit as, "Capt. Allen's Battalion of Volunteers". As the new unit was being recruited and mustered into service, its first commander, James Allen, signed official documents with the name he gave the unit, "Mormon Battalion", General Stephen Watts Kearny, in letters of reply to the unit used Allen's naming convention, calling it the "Battalion of Mormons" and "Mormon Battalion" P. St. George Cooke, commanding the Battalion under orders from Gen Kearny used the name, "Mormon Battalion" when reporting troop strengths in California.

Kentucky

 * Regiment of Kentucky Cavalry Volunteers, for 12 months; June 1846 – July 1847. Colonel Humphrey Marshall (former 2nd Lt 1. U.S. Dragoons.)
 * 1st Regiment of Kentucky Volunteers, for 12 months, "Louisville Legion"; May 1846 – May 1847. Colonel Stephen Ormsby
 * 2nd Regiment of Kentucky Volunteers, for 12 months; June 1846 – June 1847. Colonels: William R. McKee (former 1st Lt. 3rd. U.S. Artillery, killed.); Lt. Colonel Henry Clay, Jr. (former 2nd Lt. 2nd. U.S. Artillery, killed); Major Gary H. Fry (former 2nd Lt, 3rd. U.S. Infantry)
 * 3rd Regiment of Kentucky Volunteers, for during the war with Mexico; October 1847 – July 1848. Colonel Manlius V. Thomson
 * 4th Regiment Kentucky Volunteers, for during the war with Mexico; October 1847 – July 1848. Colonel John S. Williams (late Capt. of Independent Company)
 * Independent Company of Kentucky Volunteers; May 1846 – May 1847. Captain John S. Williams (served with the 6th U.S. Infantry)

Louisiana

 * Louisiana Battalion of Volunteer Artillery, for 3 months; (2 companies); August 21 – November 1845. Major Louis Gaily
 * 2nd Battalion of Louisiana Volunteer Artillery, for 6 months, (3 companies), received for 3 months, May–July 1846. Major Louis Gaily (commander 1st Battery)
 * Brigade of Louisiana Volunteers, for 6 months, (6 regiments); received, for 3 months. May and June–August 1846. Brigadier General Persifor F. Smith
 * 1st Regiment, P. F. Smith's Brigade of Louisiana Volunteers. Colonel James B. Walton
 * 2d Regiment, P. F. Smith's Brigade of Louisiana Volunteers. Colonel James H. Dakin
 * 3rd Regiment, P. F. Smith's Brigade of Louisiana Volunteers. Colonel Samuel F. Marks
 * 4th Regiment, P. F. Smith's Brigade of Louisiana Volunteers. Colonel Horatio Davis
 * 5th Regiment, P. F. Smith's Brigade of Louisiana Volunteers. Colonel Baillie Peyton
 * Independent Company of Louisiana Volunteers, for 12 months; July 1846 – May 1847. Captain Albert G. Blanchard (former 1st Lieutenant in 3rd U.S. Infantry, and Captain 3rd Louisiana Volunteers)
 * Regiment of Louisiana Volunteers, for during the war with Mexico; December 1846 – July 1848. Colonel Lewis G. De Russy (formerly Capt. U.S. Artillery and Paymaster)
 * Battalion of Louisiana Volunteers, for during the war with Mexico, (5 companies); May 1847 – July 1848. Lt. Colonel Charles Fiesca (late Major 4th Regiment Louisiana Volunteers)
 * Battalion of Louisiana Mounted Volunteers, for 12 months, (5 companies); July and August 1847 – July 1848. Lt. Colonel Walter F. Biscoe (late 2nd Lieutenant in 2nd Regiment Louisiana Volunteers)

Maryland and the District of Columbia

 * Battalion of Maryland and District of Columbia Volunteers, for 12 months, (6 companies); May 1846 – May 1847. Commanders: Lt. Colonel William H. Watson (killed at Monterey); Brevet Major Robert C. Buchanan (Captain 4th U.S. Infantry Regiment, from November 1846)
 * Regiment of Maryland and District of Columbia Volunteers, for during the war with Mexico, (8 companies); May and June 1847 – July 24, 1848. Colonel George W. Hughes (Captain and brevet Lt. Colonel Topographic Engineers)
 * 3 additional Separate Companies were attached to this Regiment:
 * Tennessee Company of Mounted Volunteers; May 1847 to July 1848. Captain C. Roberdeau Wheat (served with 2nd Dragoons; Major General Scott's bodyguard)
 * Pittsburg Company; October 1847 to July 1848. Captain Thomas A. Rowley
 * Independent Company; June 8, 1847 – August 1, 1848. Captains: James Boyd, (Captain in Watson's Battery; killed at Rio Calaboso, July 12, 1847); Joseph R. West, (served at Tampico under Colonel De Russy)

Massachusetts

 * Regiment of Massachusetts Volunteers, for during the Mexican War, January and February, 1847 – July 1848. Colonels: Caleb Cushing, (January 15, 1847: promoted to Brig. General); Isaac H. Wright (Lt Colonel to May 27, 1847).

Michigan

 * Regiment of Michigan Volunteers, for during the war with Mexico; December 1847 – July 1848. Colonel Thomas B. W. Stockton (former 1st Lieutenant, 1st. U.S. Infantry)
 * Independent Company of Michigan Volunteers, for during the war with Mexico, June 18, 1847 – June 30, 1848. Captain Morgan L. Gage

Mississippi

 * 1st Regiment of Mississippi Rifles, volunteers for 12 months; June 1846 – June 1847. Colonel Jefferson Davis (former 1st Lieutenant and Adjutant 1st. Dragoons; severe wound, at Buena Vista)
 * 2nd Regiment of Mississippi Volunteers, for during the war with Mexico; received January 1847 – July 1848. Colonels: Reuben Davis (resigned October 1847); Charles Clark (Captain to October 16, 1847)
 * 1st Battalion of Mississippi Rifle Volunteers, for during the war with Mexico, (5 companies); October and November 1847 – June 1848. Lt. Colonel James Patton Anderson

Missouri

 * 1st Regiment of Missouri Mounted Volunteers, for 12 months; (8 companies); June 1846 – June 1847. Colonel Alexander W. Doniphan
 * Battalion of Missouri Volunteers, for 12 months; (3 Light Artillery companies; 2 Infantry companies); June and July 1846 – June and July 1847. Major Meriwether L. Clark (former 2nd Lieutenant 6th U.S. Infantry and Aide de Camp to General Scott)
 * Battalion of Missouri Mounted Volunteers, for 12 months,(4 companies, first mustered in Price's regiment); August 1846 – August 1847. Lt. Colonel David Willock
 * 9 Companies of Missouri Volunteers, for 12 months; received at Fort Leavenworth August and September 1846, order of service countermanded by War Department, September 1846
 * Battalion of Missouri Volunteers for during the war with Mexico, (5 companies); May 1847 – October 1848. Lt. Colonel Alton R. Easton (late Colonel "St. Louis Legion.")
 * 3rd Regiment of Missouri Mounted Volunteers, for during the war with Mexico; July 1847 – October 1848. Colonel John Ralls
 * Battalion of Missouri Mounted Volunteers, for during the war with Mexico, (5 companies); August 1847 – November 1848. Lt. Colonel Ludwell E. Powell
 * Battalion of Missouri Mounted Volunteers, for during the war with Mexico, (5 companies); September 1847 – October 1848. Lt. Colonel William Gilpin (late Major of Doniphan's Regt.)

New Jersey

 * Battalion of New Jersey Volunteers, for during the Mexican war, (4 companies); September 1847 – July 1848. Lt. Colonel Dickinson Woodruff

New York

 * 1st Regiment of New York Volunteers, for service in California and during the war with Mexico; August–October 1848. Colonel Jonathan D. Stevenson
 * 2nd Regiment of New York Volunteers, for during the war with Mexico; November 1846 – August 1848. Colonel Ward B. Burnett (former 2nd Lt. 2nd U.S. Artillery, severely wounded at Churubusco)

North Carolina

 * Regiment of North Carolina Volunteers, for during the war with Mexico; January 1847 – August 1848. Colonel Robert T. Paine

Ohio

 * 1st Regiment of Ohio Volunteers, for 12 months; June 1846 – June 1847. Colonel Alexander M. Mitchell (former 2nd Lieutenant, 4th U.S. Infantry, wounded at Monterey)
 * 2nd Regiment of Ohio Volunteers, for 12 months; June and July 1846 – June 1847. Colonel George W. Morgan
 * 3rd Regiment of Ohio Volunteers, for 12 months; June 1846 – June 1847. Colonel Samuel R. Curtis (former 2nd Lieutenant, 7th U.S. Infantry and Adj. General of Ohio)
 * 4th Regiment of Ohio Volunteers, 1st Regiment for during the War with Mexico; May and June 1847 – July 1848. Colonel Charles H. Brough
 * 5th Regiment of Ohio Volunteers, 2nd Regiment for during the war with Mexico; September 1, 1847 – July 1848. Colonel William Irvin (late Lt. Colonel of Morgan's Regt.)
 * Independent Companies of Ohio Volunteers, for during the war with Mexico:
 * 1st Company of Mounted Men; June 1, 1847 – August 2, 1848. Captain John R. Duncan
 * 2nd Company of Foot; October 1847 – July 1848, (served with Irvin's Regt.). Captains: William Keimeally (died, reported suicide, at Rio Frio, December 21, 1847). William H. Lytle
 * 3rd Company of Foot; October 26, 1847 – July 17, 1848. Captain Robert F. Riddle

Pennsylvania

 * 1st Regiment of Pennsylvania Volunteers, for during the war with Mexico; December 1846 – July and August 1848. Colonel Francis M. Wynkoop
 * 2nd Regiment of Pennsylvania Volunteers, for during the war with Mexico, (12 companies); January 1847 – July 1848. Colonels: William B. Roberts (died in City of Mexico October 3, 1847); John W. Geary (Lt. Colonel to November 3, 1847, wounded at Chapultepec.)

South Carolina

 * Regiment of South Carolina Volunteers, for during the war with Mexico, "Palmetto Regiment"; December 1846 – June and July 1848. Colonel Pierce M. Butler (twice wounded, and killed at Churubusco)

Tennessee

 * Regiment of Tennessee Mounted Volunteers, for 12 months; June 1846 – May 1847. Colonel Jonas E. Thomas
 * 1st Regiment of Tennessee Volunteers, for 12 months, (12 companies); May and June 1846 – May 1847. Colonel William B. Campbell (former Capt. in Trousdale's Regt. in Florida War)
 * 2nd Regiment of Tennessee Volunteers, for 12 months, (8 companies); June 1846 – May 1847. Colonel William T. Haskell
 * 3rd Regiment of Tennessee Volunteers, for during the war with Mexico; October 1847 – July 1848. Colonel Benjamin F. Cheatham (late Capt. in Campbell's Regt.)
 * 4th Regiment of Tennessee Volunteers, for during the war with Mexico, (9 companies); November 1847 – August 1848. Colonel Richard Waterhouse (late Major in Thomas' Regt. Cav.)
 * 5th Regiment of Tennessee Volunteers, for during the war with Mexico, (11 companies); December 1847 – July 1848. Colonel George R. McClellan

Texas

 * General Staff of Texas Volunteers; July 1846 – October 1846. Major General (Gov.) James Pinckney Henderson.
 * 1st Regiment of Texas Mounted Rifle Volunteers, June and July, and discharged September and October 1846. Colonel John C. Hays (late Major of a Btln. in the service of Texas.)
 * 2nd Regiment of Texas Mounted Volunteers, June and July, and discharged October 1846. Colonel George T. Wood
 * 3rd Regiment of Texas Rifle Volunteers, May, June and July, and discharged August 1846. Colonel Albert Sidney Johnston (former Adjutant U.S. 6th Infantry and Adjutant General of Texas.)
 * Regiment of Texas Mounted Volunteers, for 6 months (7 companies), for frontier defence; July, and discharged September 1846. Colonel William C. Young
 * Battalion of Texas Mounted Volunteers, of (4 companies); March 1847 – June 1848. Majors comdg.: M. H. Chevallie (late of Major Hays 1st Regt.; resigned 31 August 47); Walter P. Lane (Captain to October 1847)
 * Regiment of Texas Mounted Volunteers, for 12 months and during the war; April 1847 – May 1848. Colonel John C. Hays (Col. of 1st Regt. Vols, and continued in Service)
 * Regiment of Texas Mounted Volunteers, for 6 months, for frontier defence; May 11, and discharged June 1847. Colonel John C. Hays (Col. of Regt. in Mexico)
 * Battalion of Texas Mounted Volunteers, (5 companies), for local defence; April – June 5, 1847. Major Thomas J. Smith
 * Independent Companies of Texas Volunteers:
 * 1st Mounted Company; September 25, 1845 – June 25, 1846. Captain John T. Price
 * 2nd Company of Rangers; September and December 10, 1845 and March 1846, for two periods of 3 months each – July 1846. Captain Peter Hansbrough Bell (had before served on frontier defence of Texas, under Major Hays from September 1845)
 * 3rd Mounted Company; October 1, 1845 and January 1846 – September 1846. Captain David C. Cady
 * 4th Mounted Company; May and August 1846 – September 18, 1846. Captain Ben M'Culloch
 * 5th Mounted Company; July–October 1846. Captain Eli Chandler
 * 6th Mounted Company; July 1846 – July 1847. Captain Mabery B. Gray (late 1st Lt. in Bell's co.)
 * 7th Company of Foot Volunteers (first enrolled in Mississippi); August 1846 – January 7, 1847. Captain William E. Shivors (late Capt in Johnston's 3rd Rifle Regt.)
 * 8th Rifle Company; (late Seefeld's Company of Johnston's 3rd Regt.); received September 1, 1846 – July 1, 1847. Captain P. Edward Connor (late 1st Lt. to December 1846: wounded at Buena Vista; retired May 1847.)
 * 9th J Company Volunteers (at Monterey); October 8, 1846 – October 1847.  Captain Mirabeau B. Lamar (late Division Inspector to Maj. Gen. Henderson)
 * 10th I Company Volunteers; October 1846 – October 1847. Captain Shaply P. Ross
 * 11th Mounted Company of Spies; January 31 – July 31, 1847. Captain Ben McCulloch (Major in the Staff)

Virginia

 * Regiment of Virginia Volunteers, for during the war with Mexico, (14 companies); December 1846 and January 1847 – August 1848. Colonel John Francis Hamtramck (former 2nd Lieutenant, 3rd U.S. Artillery Regiment)

Misc. volunteers

 * Battalion of "Sante Fe" Mounted Volunteers, for during the war with Mexico, (4 companies); July and August 1847 – October 20, 1848. Major Robert Walker (late Adjutant of Price's Regt. Missouri Volunteers)

U.S. Navy

 * The Home Squadron operated in the Gulf of Mexico and was lead by Commodore David Conner. Conner was appointed to command the squadron December 30, 1843. He was relieved by Commodore Matthew C. Perry on March 3, 1847. The Revenue Marine cutters listed in the U.S. Revenue Marine Service section of this list article were also assigned to the Home Squadron.
 * USS Albany (1846), Captain Samuel Livingston Breese
 * USS Bonita
 * USS Boston (1825)
 * USS Cumberland (1842)
 * USS Decatur (1839)
 * USS Electra
 * USS Etna
 * USS Falcon (1846), Lieutenant John J. Glasson
 * USS Falmouth (1827)
 * USS Flirt (1839)
 * USS Fredonia (1845)
 * USS Germantown (1846)
 * USS Hecla (1846)
 * USS Hunter
 * USS Iris (1847)
 * USS John Adams (1799)
 * USS Lawrence (1843)
 * USS Mahonese
 * USS Mississippi (1841)
 * USS Morris
 * USS Nonata
 * USS Ohio (1820)
 * USS Onkahye (1843)
 * USS Perry (1843)
 * USS Petrel
 * USS Petrita (1846)
 * USS Porpoise (1836)
 * USS Potomac (1822)
 * USS Princeton (1843)
 * USS Raritan (1843)
 * USS Reefer (1846)
 * USS Relief (1836)
 * USS St. Mary's (1844)
 * USS Santa Anna
 * USS Saratoga (1842)
 * USS Scorpion (1847)
 * USS Scourge (1846)
 * USS Somers (1842)
 * USS Spitfire (1846)
 * USS Stromboli (1846)
 * USS Supply (1846)
 * USS Tampico, Lieutenant William P. Griffin
 * USS Truxtun (1842)
 * USS Union (1846)
 * USS Vesuvius (1846)
 * USS Vixen (1846)
 * USS Washington
 * USS Water Witch (1847)
 * The Pacific Squadron operated off the Pacific coast of California and Mexico and was lead by Commodore John D. Sloat to July 29, 1846. Commodore Robert F. Stockton, July 29, 1846 – January 22, 1847. Commodore W. Branford Shubrick, January 22, 1847 – March 1, 1847. Commodore James Biddle, March 1, 1847 – July 19, 1847. Commodore W. Branford Shubrick, July 19, 1847 – May 6, 1848. Commodore Thomas ap Catesby Jones from May 6, 1848.
 * USS Columbus
 * USS Congress
 * USS Cyane
 * USS Dale
 * USS Erie
 * USS Indpendence
 * USS Julia
 * USS Levant
 * USS Lexington
 * USS Libertad >
 * USS Malek Adhel
 * USS Ohio
 * USS Portsmouth
 * USS Preble
 * USS Savannah
 * USS Shark
 * USS Southampton
 * USS Warren
 * USS Whiton
 * Battalion of Sailors, from the fleet on the Pacific coast, organized by Commodore Robert F. Stockton, for the recapture of Los Angeles, California, January 1847. Major: Stephen C. Rowan (Lieutenant U.S. Navy)
 * Artillery Company. Captain Richard L. Tilghman (Lieutenant)
 * A Company. Captain John Guest (Acting master)
 * B Company. Captain William B. Renshaw (Lieutenant)
 * C Company. Captain Benjamin F. B. Hunter (Acting Lieutenant)
 * D Company. Captain Edward Higgins (Acting Lieutenant)
 * E Company. Captain J. Fenwick Stenson (Acting Lieutenant)
 * F Company. Captain James M. Duncan (Passed Midshipman)
 * G Company. Captain John Peed (Sailmaker)
 * Sappers and Miners. Captain John Southwick (Carpenter)

U.S. Marine Corps

 * Battalion of Marines; May 1847 – January 1848. Brevet Lieutenant Colonel Samuel E. Watson. Attached to Brigadier General John A. Quitman's 4th Division consisting of volunteers from New York, Pennsylvania, and South Carolina. Served at the Battle of Chapultepec September 13, 1847.

U.S. Revenue Marine Service

 * The following Revenue Marine cutters were dispatched to serve under the command of the "Commanding General of the Army of Occupation" on May 19, 1846 under orders from the Secretary of the Treasury Robert J. Walker. The squadron was under the overall command of Captain John A. Webster, Sr., who chose Ewing as his flagship. Webster served as squadron commander until December 10, 1846 when he was taken ill by a fever. He was relieved by Captain Winslow Foster who served as squadron commander thereafter.
 * McLane. Captain William A. Howard, May 16, 1846 — June 4, 1847
 * Spencer. Captain Caleb Currier, May 16, 1846 — July 14, 1846
 * Legare. Captain N.L. Coste, May 16, 1846 — October 26, 1846
 * Woodbury. Captain William B. Whitehead, May 16, 1846 — July 9, 1846
 * Ewing. Captain Gay Moore, May 16, 1846 — April 15, 1847
 * Forward. Captain Henry B. Nones, May 16, 1846 — April 30, 1847
 * Van Buren. Captain Thomas C. Rudolph, May 16, 1846 — Oct 31, 1846
 * Four additional cutters were dispatched under either separate orders or at a later date.
 * Bibb. Captain Winslow Foster, January 7, 1847 — May 31, 1847
 * Morris. Captain Green Walden, May 16, 1846 – November 2, 1846
 * Wolcott. Captain Louis C. Fatio (to September 1, 1846), Captain Levy C. Harby (from September 1, 1846), May 16, 1846 — May 11, 1847. Used for carrying dispatches from Mexico to New Orleans, Louisiana.
 * Polk. Placed under the command of Lieutenant W.S. Ogdon, U.S. Navy, March 14, 1846 — May 3, 1846