The Land That Time Forgot was written early in Edgar Rice Burroughs’ career and is among his best books outside the Tarzan, John Carter (Barsoom), and Pellucidar series. Written during World War I, it reflects the popular passions of the times in the villainy of most of the German characters, mirrored in the aggressive assertion of the Wieroos as the dominant race of Caspak. Despite the overreliance on coincidence, stereotyped characters, and uneven prose typical of Burroughs’ work, the trilogy is a vigorous, inventive, and even provocative fantasy adventure with definite science-fiction underpinnings.

The three books form a carefully woven mystery concerning the evolutionary and reproductive structure of Caspak, with only limited information presented in the first two books. The idea that humans and beasts evolve from eggs to tadpoles, and eventually to a terminal state over a lifetime of several hundred years, is interestingly used as the basis for many of the novel’s intrigues. Unfortunately, Burroughs’ Darwinism emerges at times as racial and ethnic supremacy, though at other times he seems to question such attitudes. Such unexpected complexities, despite Burroughs’ adolescent sensibility, perhaps account for the increasing critical attention his work has received. Burroughs’ lost worlds—whether called Caspak, Mars, or Africa—are the exotic stuff that boys’ dreams are made of, existing somewhere beyond, and impervious to critical scrutiny.