"One of the Great Masters of Adventure"

"The serial, needless to say, was a hit, though no one yet knew that ERB would soon become a phenomenon. His editor at All-Story quickly asked him to write a historical novel, which the obliging author produced in a few weeks, only to have the chivalric romance rejected. Eventually, it would be revised and rejected again. Putting 'The Outlaw of Torn' aside, Burroughs took up his own new idea, its action set largely in Africa (where he had never been). Drawing on the classical legends of the heroic Romulus and Remus, who were suckled by a wolf, and adding a touch of Mowgli from Kipling’s 'The Jungle Books,' Burroughs created one of the most famous fictional characters of modern times. In the November, 1912 issue of All-Story—only a few months after the conclusion of John Carter’s adventures on Mars—there appeared, published in its entirety, 'Tarzan of the Apes.'
"Readers went crazy."

Michael Dirda in Salon writes an appreciation of Edgar Rice Burroughs.