The Eternal Lover is a fantasy-adventure novel by American writer Edgar Rice Burroughs.

An E-Text edition has been published by Edgar Rice Burroughs, Inc. and is available online.

[2] A cliff-dwelling warrior of 100,000 years ago, Nu, is magically transported to the present, falls in love with Victoria Custer of Beatrice, Nebraska, the reincarnation of his lost lover Nat-ul, and the two are transported back to the Stone Age.

The story is set in Africa, and the present-day sequences include Victoria's brother Barney Custer, protagonist of Burroughs's Ruritanian novel The Mad King, as well as Burroughs's iconic hero Tarzan from his Tarzan novels.

While the four Custer sibling novellas were first published in an alternating fashion; chronologically-speaking, the events of the two halves of The Eternal Lover/Savage occur between the two halves of The Mad King Publication order:[1] All four novellas—as they were serialized in All-Story Weekly—are in the public domain in the United States.