William Allan was born in Winchester, VA. He was the son of Thomas Allan (1802-1873) of Winchester, and his wife, Jane Dowdell (or Dowdall) George Allan (1803-1862). (Gunter; Findagrave.com) After attending a local school for his early education, William Allan enrolled in the University of Virginia and attended sessions 34-36 (1857-1860). There he studied a broad curriculum, including Greek and Latin, Modern Languages, Mathematics, Chemistry, Natural Philosophy, History and Literature, Medicine, and Anatomy and Surgery.
After graduating, William Allan taught school in Albemarle County, VA, until he enlisted in the Confederate Army at the beginning of the Civil War. (Krick) He served for the entire length of the War, under Generals Stonewall Jackson, Richard S. Ewell, and Jubal Early, and participated in many battles, including Harpers Ferry, Antietam, Chancellorsville, and Gettysburg. Allan rose to the rank of Lieutenant-Colonel and to the position of Ordnance Officer of the Army of Northern Virginia. (Gunter; War of the Rebellion)
After the War, Col. Allan worked as a bank cashier for a time. In 1866, Robert E. Lee recruited Col. Allan to join the faculty of Washington College (now Washington and Lee University) in the chair of applied mathematics. Allan left Washington College in 1873 to become the first principal of the McDonogh School, a school for poor boys, located in Owings Mills, MD.
About 1877, Col. Allan married Elizabeth Randolph Preston (1848-1933), and they had several children: Margaret R., Jannet G., John Preston, William, Joe B. (a daughter), Lucy Alexander (died young), and Thomas (died young) Allan. (1880 & 1900 U.S. Censuses)
Col. Allan was a prolific writer, and published books and articles on applied mathematics, including Notes on Rankine’s Textbook of Engineering, The Theory of Arches (1874), and The Strength of Materials, as well as books and articles on Confederate history, including History of the Campaign of Gen. T. J. (Stonewall) Jackson in the Shenandoah Valley of Virginia from November 4, 1861 to June 17, 1862 (1880), and The Army of Northern Virginia in 1862 (1892).
He died in 1889 of Bright’s Disease [chronic nephritis], after an illness of about 6 months. He was buried in the cemetery of the McDonogh Institute, with his two youngest children, who had predeceased him. His wife, Elizabeth, survived him by 44 years. She lived with her son Dr. William Allan in Charlotte, North Carolina. When she died, she was buried in Elmwood Cemetery, in Charlotte. (Gunter)
- Allan, Elizabeth tombstone, in Elmwood Cemetery, Charlotte, NC. https://www.findagrave.com/memorial/33252008/elizabeth-randolph-allan
- Allan, Jane D. tombstone, in Mount Hebron Cemetery, Winchester, VA https://www.findagrave.com/memorial/71758091/jane-d-allan
- Allan, Thomas tombstone, in Mount Hebron Cemetery, Winchester, VA https://www.findagrave.com/memorial/196616011/thomas-allan
- Allan, William. History of the Campaign of Gen. T. J. (Stonewall) Jackson in the Shenandoah Valley of Virginia from November 4, 1861 to June 17, 1862. Philadelphia: J. B. Lippincott, 1880. https://archive.org/details/historyofcampaig00alla/
- Allan, William & John Johnson. Life and work of John McDonogh & Sketch of the McDonogh School. Press of I. Friedenwald. Baltimore, Maryland, 1886.
- Allan, William. Army of Northern Virginia in 1862. Boston: Houghton, Mifflin & Co., 1892.
- “Allan, William (1837-1889).” in Alphabetical list of collectors included in the Putnam Museum herbarium biography compilation. http://www.plantsofiowa.com/BDI_collector_list.html
- Allan, William tombstone, in McDonogh Institute Cemetery, Owings Mills, MD. Findagrave.com. https://www.findagrave.com/memorial/76899241/william-allan
- Gunter, D. W., & the Dictionary of Virginia Biography. William Allan (1837–1889). (2017, February 23). In Encyclopedia Virginia. Retrieved from http://www.EncyclopediaVirginia.org/Allan_William_1837-1889.
- Krick, Robert E. L. Staff Officers in Gray; a biographical register of the staff officers in the Army of Northern Virginia. Chapel Hill, NC: The University of North Carolina Press, 2003.
- Macdonald, R.W. (ed.). “Death of Col. William Allan.” The Week. 7(12) (21 Sep 1889):45-48. https://www.mcdonogh.org/theweek/issues/archive/1880/18890921.pdf
- “United States Census, 1880,” database with images, FamilySearch (https://familysearch.org/ark:/61903/1:1:MN3B-DTX : 8 September 2017), William Allan, District 2, Baltimore, Maryland, United States; citing enumeration district ED 225, sheet 460A, NARA microfilm publication T9 (Washington, D.C.: National Archives and Records Administration, n.d.), FHL microfilm 1,254,495.
- “United States Census, 1900,” database with images, FamilySearch (https://familysearch.org/ark:/61903/1:1:MMJS-MQ5 : accessed 3 January 2020), Jennett G Allen in household of Elizabeth Allen, Lexington Township Lexington town, Rockbridge, Virginia, United States; citing enumeration district (ED) 97, sheet 1B, family 10, NARA microfilm publication T623 (Washington, D.C.: National Archives and Records Administration, 1972.); FHL microfilm 1,241,725.
- United States. War Department, Report of Lieut. Col. William Allan, C. S. Army, Chief of Ordnance, of ordnance and ordnance stores collected on the Wilderness battle-field May 5-7, . Dated December 28, 1864, in The War of the Rebellion: A Compilation of the Official Records of the Union and Confederate Armies. Washington: Government Printing Office, 1891, Ser. I, Vol. 36, Part 1, reports, document no. 286, p.1076.
- William Allan Papers, #2764, Southern Historical Collection, The Wilson Library, University of North Carolina at Chapel Hill. https://finding-aids.lib.unc.edu/02764/#d1e49