Perhaps the best known international exhibition in the Cold War period was the 1958 Exposition Universelle et Internationale de Bruxelles (Expo '58). As the first one held after World War II, it acquired broader significance: the governments of the European Western Allies—France and Britain—used the occasion to demonstrate their postwar successes, while the Axis countries—Germany, Japan, Italy—had the opportunity to refurbish their international images. Most noticeable amid the general exuberance of the fair, however, was the obvious tension between the United States and the Soviet Union, who used their pavilions to promote their rival political systems.

The theme of the U.S. exhibit, "Unfinished Business," dealt with, among other subjects, America's social issues, including segregation. Southern congressmen took offense and cut the remaining U.S. exhibition budget. As a result, the number of U.S. scientific exhibits were reduced, and Russia took over the unused U.S. space in the International Hall of Science, using it to good effect as a propaganda showcase of Soviet technological advances: it had, for example, a display on the peaceful uses of atomic energy by the Soviets, contrasted with America's use of nuclear power "for the undoing of mankind."

At the core of the Soviet exhibit were models of its newly launched Sputnik satellites, which had initiated the Russian space program the previous year, including a flight that carried a dog named Laika. Although the United States had launched its own successful satellite, Explorer, in 1958, it did not have its space artifact on display. Sputnik proved very popular with the crowds, and the Soviets used their pavilion, a high-tech tribute to communism, as an opportunity to try to convince fairgoers that a technologically and scientifically superior USSR would shortly surpass the United States in the production of material goods. America was better prepared in subsequent world fairs.

Aside from the Cold War cultural rivalries, the exposition was notable for the variety of scientific products demonstrated, including an audio encyclopedia, an electronic dictionary, pasteurized cheese, magnetic tape capable of transmitting millions of characters in a few seconds, and a postal machine that could sort a thousand checks in 15 minutes. Belgium itself, which had held the fair to promote its economic growth, impressed audiences with its centerpiece, the towering Atomium—a futuristic building highlighting the positive side of the atomic age —and its chocolate, producing five tons of it each day of Expo '58.