The Wizard of Oz or simply The Wizard is a fictional character in the Land of Oz created by American author L. Frank Baum and further popularized by the classic 1939 movie.
The Wizard is one of the characters in The Wonderful Wizard of Oz. Unseen for most of the novel, he is the ruler of the Land of Oz and highly venerated by his subjects. Believing he is the only man capable of solving their problems, Dorothy Gale and her friends travel to the Emerald City, the capital of Oz, to meet him. Oz is very reluctant to meet them, but eventually they are granted an audience. Every time the Wizard appears in a different form, once as a giant head, once as a beautiful fairy, once as ball of fire, and once as a horrible monster.
Eventually, it is revealed that Oz is actually none of these things, but rather an ordinary, American man who has been using a lot of elaborate magic tricks and props to make himself seem "great and powerful." When revealed, Oz explains that his real name is Oscar Zoroaster Phadrig Isaac Norman Henkel Emmannuel Ambroise Diggs. To shorten this name, he used only his initials (O.Z.P.I.N.H.E.A.D.), but since they spell out the word "pinhead", he shortened his name further and called himself "Oz". Working as a magician in the United States, he wrote OZ on the side of his hot air balloon for promotional purposes. One day his balloon sailed into the Land of Oz, and found himself worshipped as a great sorcerer. As Oz had no leadership at the time, he became Supreme Ruler of the kingdom, and did his best to sustain the myth.
He leaves Oz at the end of the novel, again in a hot air balloon. After the Wizard's departure, the Scarecrow is briefly enthroned, until the rightful hereditary ruler of Oz, Princess Ozma, is freed from the witch Mombi at the end of The Marvelous Land of Oz.
In The Marvelous Land of Oz, the Wizard is described as having usurped the throne of King Pastoria and handed over the baby princess to Mombi. This did not please the readers, and in Ozma of Oz, although the character did not appear, Baum described Ozma's abduction without including the Wizard as any part of it.
The Wizard returns in the novel Dorothy and the Wizard in Oz. With Dorothy and the boy Zeb, he falls through a crack in the earth; in their underground journey, he acts as their guide and protector. When Ozma rescues them from the underground kingdoms, he recounts his story of becoming the ruler of Oz, and Ozma explains that before the witches usurped her grandfather's throne (an occurrence happening long before the wizard arrived), the ruler of Oz had always been known as Oz or (if female) Ozma. Ozma then permits him to live in Oz permanently. He becomes an apprentice to Glinda, the most powerful magic-worker in Oz. Ozma decrees that, besides herself, only The Wizard and Glinda are allowed to use magic.