This chaotic infographic was created by the Toronto-based Comparative Synoptical Chart Company, begun by Arthur Hodgkin Scaife, in the late 1890s and published and filed with the Library of Congress in 1897. The purpose of the graphic, in spite of what one might at expect, is not to stupify you with information overload. Instead, the goal was to apply the 'Scaife Synoptical Method' to the martial history of the Civil War and create one single graphic that explained the the unfolding of events and contributing factors between 1861 and 1865.
As far as I can tell, the Scaife Synoptical Method's central axiom was to compress as much information as possible into a single graphic, even at the loss of readability. This graphic, "History of the Civil War in the United States 1860-1865", doesn't actually include all possible information pertaining to the war, as some bloggers have been claiming. But it does include the information most pertinent to the progress of the war: value of the Confederate and Union dollars; size of the armies; conscriptions and losses; critical legal affairs passed; skirmishes, battles, and army movements.
Part of the Scaife Method's difficulty with readability seems to be a simple matter of orientation, displaying information in ways that are uncommon in the 21st century and that feel a little counterintuitive. Each state playing a major role in the war is represented by a column, typically running south-north from left to right, flanked on each side by columns displaying Confederate and Federal contributing factors. Time runs upwards, which also feels odd to me, and though each month is ticked off in equal measure, the size of each state column and the distance between battle locations within each column seems to be fairly arbitrary and confusing. There's a similar situation going on with the Federal and Confederate army lines (yellow and green, respectively) and though I imagine there is some significance associated with which side of the battle line is shaded, I don't know enough about the Civil War and its specific battles to pick out a pattern.
Nevertheless, once you've oriented yourself to the workings of this massive chart (the digitized image of which is larger than 2'x3') , its specific, mercilessly inclusive consistency is fabulous and inspiring, even if only because you really want to figure out what it is saying. The level of articulation beckons you to get lost and enjoy the details of each battle and army and location, while the overall pattern is also fascinating and paints an irritatingly futile image of war.
But there is something even more profound about this chart that is, surprisingly, not included in its massive spread of data: the location of it as an evolved data visualization tool in the history of drawings and images. First consider that, in all the history of architecture and drawings, the plan (both urban and single-building) and section, as we know them, were only developed around the turn of the sixteenth century. The axonometric drawing would be something architects developed and played with throughout the following century. The first ever infographic—a graphic tool used to visualize multiple types of data simultaneously—was created in the early 1870s by Francis Amasa Walker, meaning it took more than three hundred years to understand the potential for image-based depictions of information. His seminal infographics use census information to create maps of the US based on race, income, gender, population density, &c. And in a short twenty years after Walker, Arthur Schaife's company and its trademark data visualization method have created this groundbreaking graphic.
As I mentioned regarding the seemingly arbitrary proportion of each column, this "chart" is an impressively abstracted view of both geography and data incredibly removed from actual representations of geography or movements. (For a stark confrontation of the two representative methods check out the difference between the data portion of the graphic and the geographic map at the lower part of the chart.) The inclusion of army size and inflation as parallel trends is another fascinating addition, each represented as separate trends for each army not graphically interacting with the central data, allowing the reader to determine meta trends for themselves. Also fascinating to me is the inclusion of time as an axis, which transcends simple formulation of a 'timeline'. Geographically speaking many of these lines are armies tracing themselves back and forth across different states as each experiences reciprocal losses and defeats. But depicted in these curious columns, moving upwards along a time axis, they reveal the ridiculous nature of this tit-for-tat relationship in a way that is astoundingly obvious to any reader.
Ultimately this overwhelming infographic is a landmark artifact in the history of images, drawings, and data visualization. Its abstraction and compilation of different types of data is fascinating and, even by modern standards, rich with nuance and meaning. Check out the high res zoomable version from the Library of Congress, or this large and downloadable one from Slate.