Bowie, Effie Gwynn. Across the Years in Prince George’s County: A Genealogical and Biographical History of Some Prince George’s County, Maryland and Allied Families. Richmond: Garrett and Massie, nd. A good starting place to figure out who married whom, who were neighbors to whom, etc. One caveat: this is a genteel book by a genteel 20th c. woman, so scandalous family members are often simply edited out. In one case I’ve looked into, a son who made a scandalous marriage, then died young, is said to have “gone west”!
Emerson, Sue. Wha’s Like Us: Magruders in America. (Privately published CD, 2007.) An attempt to assemble the genealogy of all know descendants of Alexander Magruder…which is, of course, nigh on impossible. It’s a place to start in a search for ancestors, but be sure to find corroborating evidence. For availability see Wha’s Like Us & Magruders in American available again.
Ewell, Alice Maude. A Virginia Scene, or Life in Old Prince William. Lynchburg: J.P. Bell Co., 1931. Repr. Prince William County Historical Commission, n.d. An excerpt about her grandmother was published as “Ellen McGregor Ewell,” Yearbook of the American Clan Gregor Society IV (1915): 39-44. [gathering of 1914] (See link to ACGS Yearbooks in side bar of the home page or blog posts.) Ellen McGregor Ewell was born in Prince George’s County, Maryland, the only daughter of John Smith “Captain Jack” Magruder, who in 1820 changed all his children’s names to McGregor. Roderick and Nathaniel McGregor, mentioned elsewhere on the site, were two of Ellen’s brothers.
Kurz, Charles G. “McGruder Lineage in Scotland to Magruder Family in America.” Yearbook of the American Clan Gregor Society LXIII (1979) 53-72. [gathering of 1978] Kurz2 Kurz is generally reliable, though he repeats the ACGS line on Magruder descent from Clan Gregor. The “Gillespie the Cruiter” theory has never been backed up by a shred of evidence. Get past that and this is a very useful source.
Kurz, Charles G. “Margaret Campbell of Keithick.” Yearbook of the American Clan Gregor Society LXII (1978) 55-65. [gathering of 1977] The lineage of Alexander Magruder’s mother. Kurz1
See link to American Clan Gregor Society Yearbooks in the sidebar. Years on the index page indicate which gathering of the society is included; publication date is the following year. Historical sketches taper off in the 1980s, but earlier decades are a good resource, if carefully used. See What About Clan Gregor? & American Clan Gregor Society Yearbooks & how to use them
Kurz, Charles G. Research notebooks. American Clan Gregor Society Collection, Series IX, Box 10. University of Baltimore, Langsdale Library Special Collections.
MacGregor, Gordan A.C. The Red Book of Perthshire. Rev. edition. Privately published, 2008. Electronic book. 491-492. A genealogy of every family that held land in Perthshire up to the 19th c., along with cadet branches including thousands of individuals–well researched and documented. Available for purchase from the author.
MacGregor, John. “The McGrouthers of Meigor in Glenartney.” The Genealogist XXXV (Jan 1919): 65-81. Also available as a pamphlet reprint, McGrouthers of Meigor. A very good source, though recent researchers find fault with some details.
MacGregor, Martin. “A Political History of the McGregors before 1571.” PhD dissertation, University of Edinburgh, 1989.
MacGregor, Martin. “The View from Fortingall: The Worlds of the Book of the Dean of Lismore.” Scottish Gaelic Studies 22 (2006) 35-85.
Magruder, C.C. Colonel Ninian Beall. Washington: Historical Papers of the Society of Colonial Wars in the District of Columbia, No. 6 (1911). [pamphlet] Reprinted by Bibliolife, 2011. Bealls and Magruders intermarried for at least ten generations in Maryland.
Magruder, Caleb Clarke Jr., “Nathaniel Magruder of Dunblane,” Yearbook of the American Clan Gregor Society, 1917 VI (1917): 20-46. [gathering of 1916] Based on a survey of wills through several generations, this is a highly useful article, though it should not be relied on in every detail. You should check the original sources for the accuracy of any detail that’s important to you, and keep in mind that only wills were referenced. Includes Nathaniel’s children, grandchildren, great-grandchildren, and some great-great grandchildren–a list that encompasses Magruders (including the family that changed their name to McGregor), the Hamiltons and Watterstons, and Bowies who descended from Nathaniel’s granddaughter, Ursula Burgess.
Magruder, Henry Latham. Correspondence. ACGS Series IX, Box 10. University of Baltimore Special Collections. Henry Latham Magruder corr 1 Henry Latham Magruder corr 1 Henry Latham Magruder originated the “Gillespie the Cruiter” theory, but offers no evidence in his letters. In fact, he argued for an American Magruder association, rather than a MacGregor association.
McGregor Family Correspondence, 1857-1984 (bulk 1860-1862). Huntington Library and Art Gallery, San Marino, California. (https://hdl.huntington.org/digital/collection/p15150coll7/search/searchterm/mcgregor : accessed 14 March 2021). More info here blog post 10 Jan 2021.
McGruther, Duncan. Wha’s Like Us: MacGrouthers in Scotland before 1855. Self-published, 2007. 14-17, 46-53, 73-86. For availability see note below. Don searched public records for all early references to MacGrouthers (in many spellings!). This book compiles his findings and is the best source of information on our family’s origins.
Sarson, Steven. “Yeoman Farmers in a Planters’ Republic: Socioeconomic Conditions and Relations in Early National Prince George’s County, Maryland.” Journal of the Early Republic 29:1 (Spring 2009): 63-99. George and Sarah Magruder of Anchovie Hills (described as “an economically average small yeoman family”), are detailed on pp. 79-81. Now available as a pdf from Knowing Our History: African American Slavery and the University of Maryland. (Thanks to Jill Magruder Gatwood for finding that link.)
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Magruder's Landing 
I’m the 11th great grandson of Alexander magruder I’ve been doing a family tree and see that they are from Scotland. I was just wondering is Alexander magruder part African American??? I am dark but tan and I’m German swiss and Scottish so far is what I’ve found. I seen an article that said researching African American descent could some one tell me please. I’m Jason Christlieb son of Jay Edward Christlieb grandson. Of Chrales Edward Christlieb
Hi Edward. Thanks for writing. Alexander McGruther/Magruder was a Scot, born about 1610, transported as a prisoner of war in 1651 or 1652. By the time of his death he owned one enslaved African man, called Sambo in the inventory of Magruder’s estate, and from that time until Emancipation the majority of his descendants held people in slavery. So there was a lot of mixing of the races, though rarely acknowledged. Alexander has many Af-Am descendants who are just beginning to trace their genealogy. I am white, and when I tested my DNA I discovered Af-Am relations. It can be hard to find the precise parentage, however, since the births were not recorded. It’s especially difficult in Maryland b/c by the time of Emancipation very few enslaved people shared their surname with the last slave owner. Sue Emerson’s massive Magruder genealogy shows only recorded descendants, of course, and the name Christlieb appears only once, when a woman named Lou E Christlieb (1881-1967) married James Garrard Bedford im Mansfield IL. Emerson’s work is not always accurate (she tried to find every recorded descendant of Alexander and the PDF is a couple thousand pages long!) but can still provide a place to start looking. Do those names ring any bells?