A landmark use of thematic mapping to present U.S. census data. Intended to demonstrate the wildly uneven distribution of slaveholding in Virginia and thereby influence the secession debates of 1861.

The map depicts Virginia and its counties in outline, with a figure in each county indicating the number of slaves as a percentage of the overall population, from 0% in far northern Hancock to a stunning 74% in Nottoway. Each county is also correspondingly shaded, with each shade indicating a particular decile (So, for example, the darkest shade is reserved for the two counties with slave populations between 70 and 80%, and white for those below 10%.) The data is taken from the United States Census of 1860 and represents the first attempt to use census data as the basis of a thematic map. The novelty of the technique is reflected in a rudimentary error pointed out by at least one observer: “the percentages of slaves in many of the counties are incorrect [i.e., too high] because the tabulation omitted free blacks from the county totals.”

The map’s shading makes exquisitely clear that slaveholding was heavily concentrated in Virginia’s eastern and southern counties, whose geography was far better suited to a plantation economy than that of the mountainous western part of the state. During the crisis of 1860-61 the intensity of slaveholding in the eastern and southern counties correlated rather strongly with secessionist sentiment, whereas the western counties tended pro-Union. Susan Schulten has suggested—and I concur—that the map was designed to capitalize on this fact and influence the secession debate in Virginia:

“The map sends two mutually reinforcing messages about the crisis in Virginia. First, it made undeniable just how much slavery divided the interests of Virginians along geographical lines. Second, the shading of the state largely matched the divisions regarding secession, with lighter areas as comparative strongholds of unionism and darker areas sympathetic to secession.” (Schulten, “The Cartography of Slavery and the Authority of Statistics,” p. 21)

Supporting this view is the date printed on the map: June 13, 1861, just weeks after Virginia’s voters had ratified secession and while the fate of the low-slavery, more pro-Union western counties hung in the balance. Indeed at the August 1861 Second Wheeling Convention, following Virginia’s secession from the Union in May, many of these low-slavery western counties voted in turn to secede from Virginia and reenter the Union as the State of “Kanawha.” After a long political process, this new state—now named West Virginia—was admitted to the Union in 1863. Manuscript additions to this map by an early owner reflect this: A notation to the western counties reads “Western Virginia. (Chartered Dec. 10 ’62).” (The date refers to the date Congress passed the act enabling the state’s accession, contingent on revisions to its constitution.) The owner has also underlined in ink the names of the 48 counties comprising the new state and highlighted its boundaries.

The actual influence of the map is impossible to assess. It does however seem to have had rather wide distribution among influential Unionists. Susan Schulten has documented presentation copies to, among others, Secretary of the Navy Gideon Welles, Chief Engineer of the Army Joseph Gilbert Totten, and French charge d’affaires M. de Geoffrey. Oddly these are all signed by William Robert Palmer of the Topographical Engineers, who in one case seems to identify himself as the author of the map. (See Susan Schulten, “The Coast Survey maps of slavery: new discoveries!” at mappingthenation.com.)

Publication history
Though the map was copyrighted by commercial lithographer Henry Graham, it has the stark, functional appearance of a government publication, with the lettering of the title in particular reminiscent of the work of the U.S. Coast Survey. Indeed, it almost certainly was a Coast Survey production: At lower right it is signed in print “Drawn by Edwin Hergesheimer,” one of several German emigres working for the Coast Survey in the Civil War era. Further, Coast Survey Superintendent Alexander Bache was a staunch abolitionist and Unionist who later became a leader of the United States Sanitary Commission. That organization’s mission—“for the benefit of the sick and wounded soldiers” mirrors the map’s assertion that it was “Sold for the benefit of the sick and wounded of the U.S. Army.”

Stephenson and McKee suggest the map was “printed in several editions in 1861,” but I know of just two. The second edition adds a printed border delineating the western counties and labels them “Kanawha,” implicitly endorsing their secession from Virginia. Though still dated June 13, 1861 it bears a certification by the Census Superintendent Kennedy dated September 9, 1861. It was almost certainly issued between September and December of that year, as the “Kanahwa” name was soon superseded.

Presumably building on the success of the Virginia map, also in 1861 Hergesheimer produced a map depicting the distribution of slavery across the entire South, which like its predecessor was sold to help fund the care of sick and wounded soldiers.

The Virginia map is rare on the antiquarian market: None are listed on Antique Map Price Record, while Rare Book Hub lists but a single impression, sold at Swann Galleries in 2003.

References
Grim and Block, Torn in Two, pp. 25-28. Phillips, Maps of America, p. 989 (June 13, 1861). Stephenson and McKee, Virginia in Maps, pp. 192, 211. Wooldridge, Mapping Virginia, #140 (p. 149). Not in Phillips, Virginia Cartography or Stephenson, Civil War Maps. Excellent background from Susan Schulten, “The Cartography of Slavery and the Authority of Statistics,” Civil War History, vol. X no. 1 (March 2010), pp. 5-32.