The Story of Mankind revolutionized former methods of telling history. While it received the first Newbery Medal for the most distinguished contribution to American literature for children, critics and public alike hailed it as a book for all ages. Van Loon recounts history as living news, relating everything in the past to the present. From Western civilization's earliest times through to the beginning of the twentieth century, he emphasizes the people and events that changed the course of history, writing informally to make world history wonderfully alive and exciting.

Of this book the author writes, "The entrance of America upon the scene of international politics as the most important actor...convinced me that a proper and reasonable understanding of historical cause and effect was the most important factor in the lives of the rising generation. And so my book...treats the entire history of the human race as a single unit...It begins with the dim and hardly understood realm of the earliest past; it can be continued forever."