What is the first name of "The Phantom of the Opera"?

Erik (also known as The Phantom of the Opera, commonly referred to as The Phantom) is the title character from Gaston Leroux's novel Le Fantôme de l'Opéra (1909), best known to English speakers as The Phantom of the Opera. The character has been adapted to alternate media several times, including in the 1925 film adaptation starring Lon Chaney, the 1943 remake starring Claude Rains and Andrew Lloyd Webber's musical.

In the original novel, few details are given regarding Erik's past. The novel confirms that Erik has traveled to multiple countries including France, Russia, and Persia, learning various arts and sciences from each region. Erik himself laments the fact that his mother was horrified by his birth deformity, and that his father, a true master mason, never saw him. Most of the character's history is revealed by a mysterious figure, known through most of the novel as The Persian or the Daroga, who saved Erik's life in Persia, and followed Erik to Paris; other details are discussed in the novel's epilogue (e.g., his birthplace is given as a small town outside of Rouen, France).