Yellow Knight of Oz (c.1930)

Sir Hokus of Pokes grows bored with life in the Emerald City, and he and the Comfortable Camel set out for some adventure. Meanwhile a boy named Speedy blasts his way to Oz in a homemade rocket ship, where he finds himself in the underground kingdom of Subterranea. Sir Hokus rescues the Princess Marygolden and finds a shift in his identity and learns that his memories of Merrie Olde England are false.

 Market value of this Oz title from various retailers