1. Some portions of this article were developed with the aid of ChatGPT, an AI-based writing assistant, to improve clarity, coherence and reader engagement.

2. William Guilford Pomeroy, Jr. founded the American Pomeroy Historic Genealogical Association, Syracuse, New York (www.americanpomeroys.org). The Association’s mission is to promote interest in and study of American history through genealogical research; to preserve the heritage of the North American Pomeroys and their allied families by conducting research, collaborating with other researchers.

3. Frederick Masonhimer Bible Records, ca. mid-1820s, “Family Record” pages; privately held by the American Pomeroy Historic Genealogical Association, Syracuse, New York. Previously held by Grace C. Santmyers, great granddaughter of Frederick Masonheimer.

4. "Fredk Masonheimer," Company Muster-out Roll card, Co. I, 2nd Pennsylvania Regiment, 20 July 1848; digital images, FamilySearch (https://www.familysearch.org/search/collection/1987567 : accessed 30 July 2024), from "United States Mexican War Index and Service Records, 1846–1848," National Archives and Records Administration (NARA), Washington, D.C. citing NARA microfilm publication M1028, roll 12.

5. 1830 U.S. census, Frederick County, Maryland, p. 232 (stamped), Line 8, Frederick Messenheimer; digital images, Ancestry (https://www.ancestry.com : accessed 11 September 2024); citing National Archives and Records Administration microfilm publication M19, roll 57.

1840 U.S. census, Allegheny County, Pennsylvania, Indiana Township, p. 182 (stamped), Line 26, Fred Masenhamer; digital images, Ancestry (https://www.ancestry.com : accessed 11 September 2024), citing National Archives and Records Administration microfilm publication M704, roll 439.

RootsMagic (ver. 7) database, "Santmyers," compiled by and held by the American Pomeroy Historic Genealogical Association, Syracuse, New York., citing the Frederick Masonhimer family.

6. "Fredk Masonhimer," Company Muster-in Roll card, Co. I, 2nd Pennsylvania Regiment, 4 January 1847; digital images, Ancestry (https://www.ancestry.com/search/collections/2058: accessed 11 September 2024), from "U.S., Compiled Military Service Records for American Volunteer Soldiers, Mexican War, 1845–1848," citing National Archives and Records Administration (NARA), Washington, D.C, Record Group 94, microfilm publication M1028, roll 11.

Allegheny County, Pennsylvania, Orphans' Court Docket Volume 7, Estate of the Minor Children of Frederick Mesonheimer dec’d, page 472, affidavit, 12 February 1849; Orphans' Court, Pittsburgh. It is stated in this record that Frederick Mesonheimer was a Private in Capt. Porter’s Company 2nd Regiment Pennsylvania Volunteers.

7. Randy W. Hackenburg, Pennsylvania in The War With Mexico The Volunteer Regiments (Pennsylvania: The White Maine Publishing Company, 1992), pp. 23-25.

General Winfield Scott's Advance on Mexico City," U.S.-Mexican War, University of Texas at Arlington Libraries Special Collections (https://libraries.uta.edu/usmexicowar/node/4877 : accessed 12 September 2024).

8. Allan Peskin (Ed.), Volunteers: the Mexican War journals of Private Richard Coulter and Sergeant Thomas Barclay, Company E, Second Pennsylvania Regiment (Ohio: The Kent State University Press, 1991), p. 113 .

K. Jack Bauer, The Mexican War 1846-1848 (Nebraska: University of Nebraska Press, 1974), p. 268.

9. "Fredk Masonheimer," Company Muster-out Roll card, Co. I, 2nd Pennsylvania Regiment, 20 July 1848, FamilySearch.

Allan Peskin (Ed.), Volunteers: the Mexican War journals of Private Richard Coulter and Sergeant Thomas Barclay, Company E, Second Pennsylvania Regiment (Ohio: The Kent State University Press, 1991), p. 114. The Castle was used as a general hospital.

10. Benj. F. Dutton, “Orders—No. 1” The Pittsburgh Post (Pittsburgh, Pennsylvania), 08 January 1847, p. 2, col. 6.

“The Weekly Delta,” New Orleans Weekly Delta, 25 January 1847, p.2, col. 1; digital images, Newspapers.com by Ancestry (https://www.newspapers.com : accessed 23 October 2024).

11. Randy W. Hackenburg, Pennsylvania in The War With Mexico The Volunteer Regiments, p. 15.

12. Randy W. Hackenburg, Pennsylvania in The War With Mexico The Volunteer Regiments (Pennsylvania: The White Maine Publishing Company, 1992). The author provides a map to scale on the backside of the book jacket.

13. Erna Risch, Quartermaster Support of the Army; A History of the Corps, 1775-1939 (Washington, D.C.: Quartermaster Historian's Office, Office of the Quartermaster General, 1962), digital images, Internet Archive (https://archive.org : accessed 12 September 2024), pp. 291-293.

K. Jack Bauer, The Mexican War 1846-1848 (Nebraska: University of Nebraska Press, 1974), pp. 259-260.

14. "Frederick Massinghamer," Company Muster Roll card, Co. I, 2nd Pennsylvania Regiment, November & December 1847; digital images, Ancestry (https://www.ancestry.com/search/collections/2058: accessed 11 September 2024), from "U.S., Compiled Military Service Records for American Volunteer Soldiers, Mexican War, 1845–1848," citing National Archives and Records Administration (NARA), Washington, D.C, Record Group 94, microfilm publication M1028, roll 11. This card indicates that Frederick was “Absent Sick.”

Capt. Robert Porter, letter regarding the death and cause of death of Fred Masonheimer, witnessed, 10 May 1848, Co. I 2nd Regt. Penna Volunteers, U.S. Army, Mexican War; digital photocopy, purchased from National Archives, 1984; privately held by American Pomeroy Historic Genealogical Association, Syracuse, New York. This letter states that Frederick died of diarrhea.

15. Vincent J. Cirillo, "More Fatal than Powder and Shot: Dysentery in the U.S. Army during the Mexican War, 1846-48," Perspectives in Biology and Medicine, Vol. 52, no. 3 (Summer 2009): 400–413; database, National Library of Medicine (https://pubmed.ncbi.nlm.nih.gov/19684375) : accessed 12 September 2024), doi:10.1353/pbm.0.0097. This source from the online page containing the article’s abstract.

Allan Peskin (Ed.), Volunteers: the Mexican War journals of Private Richard Coulter and Sergeant Thomas Barclay, Company E, Second Pennsylvania Regiment (Ohio: The Kent State University Press, 1991), p. 115.

16. Lieutenant Colonel William Preston, Journal in Mexico, (privately printed, n.d.), p.22. Lt. Col. William Preston was a volunteer of the 4th Kentucky Regiment. His journal dates from November 1, 1847 to May 25, 1848.

Allan Peskin (Ed.), Volunteers: the Mexican War journals of Private Richard Coulter and Sergeant Thomas Barclay, Company E, Second Pennsylvania Regiment (Ohio: The Kent State University Press, 1991), P. 115.

Descendants of Mexican War Veterans, Historic Sites of the U.S.-Mexican War (https://www.dmwv.org/mexwar/mwsites/mexsites.html : accessed September 12, 2024), “Perote.”

17. Frederick Masonheimer, gravestone photograph, 21 January 2004; privately held by the American Pomeroy Historic Genealogical Association, Syracuse, New York.

18. RootsMagic (ver. 7) database, "Santmyers."

19. United States Old War Pension Index, 1815-1926, NARA microfilm publication T316 (Washington, D.C.: National Archives and Records Administration, n.d.), roll 4, pension index card for Frederick Mesanheimer (Pvt., Co. I, 2 Regiment Pa, Mexican-American War); digital images, FamilySearch (https://www.familysearch.org : accessed 16 October 2024). Elizabeth Mesanheimer (widow) filed for pension May 1848.

Frederick Mesonheimer, pension payment record, p. 181 (handwritten), Ledgers of Payments, 1818-1872, to U.S. Pensioners Under Acts of 1818 Through 1858, NARA microfilm publication T718, roll 22, Records of the Accounting Officers of the Department of the Treasury, Record Group 217; digital images, Ancestry  (https://www.ancestry.com: accessed 16 October 2024), citing the U.S., Revolutionary War Pensioners, 1801-1815, 1818-1872 collection.

Allegheny County, Pennsylvania, Orphans' Court Docket, Vol. 7, p. 472, 12 February 1849; Orphans' Court, Pittsburgh, Pennsylvania; digital images, FamilySearch (https://www.familysearch.org : 16 October 2024), citing the Pennsylvania Probate Records, 1683-1994 collection. This bounty land was valued at approximately $108.

20. Allegheny County, Pennsylvania, Orphans' Court Docket, Vol. 7, p. 471, 12 February 1849; Orphans' Court, Pittsburgh, Pennsylvania; digital images, FamilySearch (https://www.familysearch.org : 16 October 2024).

1850 U.S. census, Allegheny County, Pennsylvania, population schedule, p. 324, dwelling 160, family 160, Elizabeth Masonhammer; digital images, Ancestry (https://www.ancestry.com : accessed 16 October 2024), citing National Archives and Records Administration microfilm publication M432, roll 744.

21. RootsMagic (ver. 7) database, "Santmyers."

22. Ibid.

23. Ibid.