One World is a travelogue written by Wendell Willkie and originally published in 1943. It is a document of his world travels and meetings with many of the then-Allies heads of state as well as ordinary citizens and soldiers in locales such as El Alamein, Russia, and Iran.

Especially emphasized is the position of China in the world after the war; involved in a civil war between Nationalists and Communists, Willkie prophesies that whichever power achieves victory will make China a force to be reckoned with. It is the duty of the United Nations (the Allies, not the organization) to make sure that power is not only friendly to American and other Allied interests, but also that it is powerful enough to help the Chinese, the world's largest people group at the time this is written.

One World was highly popular in its time and sold millions of copies.