As an underwater fantasy, Baum's The Sea Fairies can be classed with earlier books with similar themes, like Charles Kingsley's The Water-Babies (1863), and successors too, like E. Nesbit's Wet Magic (1913).

In 1905, however, a musical setting of Tennyson's poem for female chorus and orchestra, composed by Amy Beach, was in performance; the title may have stuck in the back of Baum's mind.

They see amazing sights in the land of Queen Aquarine and King Anko (including an octopus who is mortified to learn that he's the symbol of the Standard Oil Company).

They also encounter a villain called Zog the Magician, a monstrous hybrid of man, animal, and fish, one of the very few absolutely irredeemable, pure-evil characters in Baum's writings.

The Sea Fairies was intended to be the first in a new series of fantasy novels, which Baum and Reilly & Britton continued the next year with Sky Island.

In 1985, an independent producer commissioned a script based on The Sea Fairies as a follow-up to the movie Return to Oz, but because of the films poor reception, the project was apparently dropped.