In 1938, the day after Sudetenland Germans broke off relations with Czechoslovakia, Germany's Chancellor Adolph Hitler gave yet another rousing speech about the importance of self-determination. Citing American President Woodrow Wilson's Fourteen Points, Hitler and others such as Sudeten German leader Konrad Henlein made clear that the borders of Germany were not what they should be. Hitler had set the ultimatum of October 1 as the hand-over of the Sudetenland, which was demographically German, to Germany, and it looked as if the rest of Europe were going to agree.

Hitler's Demands Spark Demographic Study Most newspapers reported lightly on the speech, focusing more on the significant rioting as introduction of Czechoslovak troops into the region.

Gilbert Hovey Grosvenor, editor of National Geographic for nearly forty years, happened upon the story, and it put a thought into his head: What would Europe look like if state borders actually followed the bounds of national majority?

A new story by Jeff ProvinePreempting a story about the modernization of Hawaii, Grosvenor leaped into the project with many of his staff. They followed census data and made international calls, simply asking local editors what they thought each town would prefer. In the October 1938 issue, Grosvenor published his map, which gave a similar, yet ghostly, outline of Europe. The often fought-over Alsace-Lorraine between France and Germany was split, with a much larger area given to Luxembourg. Poland shifted slightly southeast. The Balkans followed much of their divides from being broken up in 1918 but with wider boundaries for Bosnians. Other people groups had countries that did not exist, such as the Basque of Spain.

After his takeover of Sudetenland, Hitler came upon the article and used it as propaganda, saying that even the Americans agreed. Much of Europe was unsettled by the thought of lines being shifted, while in the United States, the map was noticed only with anthropological interest and general academic humming. In the following months, Grosvenor would produce a series of such maps for Africa, the Middle East, South Asia, and the many Native American settlements in western United States and Canada.

World War II swept across Europe, Africa, and the Pacific for the next six years. As it came to an end, diplomats began arguing over the reassigning of borders. When the old National Geographic map was shown to him, Franklin Roosevelt was impressed with his predecessor Wilson's ideas of giving people self-determination, so much so that he was willing to overlook its use by Hitler. He pushed for such restructuring during the Yalta Conference, and Truman pushed harder at Potsdam. As the United Nations took form, these principles became critical to international policy, causing several borders to be reshuffled. The later National Geographic maps helped create the numerous nations of Africa and India during decolonization, following demographic populations rather than old imperialistic treaties.

With minimal reason for civil disputes (excluding internal affairs, such as the Chinese Civil War and the Restructure of Ireland of the 1980s), most wars during the latter part of the twentieth century were blocked by means of UN peacekeepers defending borders and diplomats discussing alternatives. Some instances required further breakup of nations, such as the dissolution of Iraq into Sunnistan, Kurdistan, and Iraq proper in 1963 and North and South Sudan in 1972. Other instances, such as the Korean Police Action, ensured that the people of Korea were properly represented in democratic election of their pseudo-socialist republic in 1950.