Via Slate: “This “Histomap,” created by John B. Sparks, was first printed by Rand McNally in 1931. (The David Rumsey Map Collection hosts a fully zoomable version here.) (Or Click on the image and use your mouse to zoom in.) This giant, ambitious chart fit neatly with a trend in nonfiction book publishing of the 1920s and 1930s: the “outline,” in which large subjects (the history of the world! every school of philosophy! all of modern physics!) were distilled into a form comprehensible to the most uneducated layman. The 5-foot-long Histomap was sold for $1 and folded into a green cover, which featured endorsements from historians and reviewers. The chart was advertised as “clear, vivid, and shorn of elaboration,” while at the same time capable of “holding you enthralled” by presenting:
the actual picture of the march of civilization, from the mud huts of the ancients thru the monarchistic glamour of the middle ages to the living panorama of life in present day America.
The chart emphasizes domination, using color to show how the power of various “peoples” (a quasi-racial understanding of the nature of human groups, quite popular at the time) evolved throughout history.”