Instructive, amusing, colorful--pictorial maps have been used and admired since the first medieval cartographer put pen to paper depicting mountains and trees across countries, people and objects around margins, and sea monsters in oceans. More recent generations of pictorial map artists have continued that traditional mixture of whimsy and fact, combining cartographic elements with text and images and featuring bold and arresting designs, bright and cheerful colors, and lively detail. In the United States, the art form flourished from the 1920s through the 1970s, when thousands of innovative...