Mattel's action figure line Masters of the Universe was selling extremely well, and Filmation had animated a few early adverts to promote the figures. Looking for a way to further increase the success of Masters of the Universe they asked Filmation to go beyond animating mere toy adverts, and create sixty-five episodes of what was to become known as He-Man and the Masters of the Universe.
The success of the Masters of the Universe toyline and show led to the spin-off series, She-Ra Princess of Power. She-Ra, He-Man's twin sister, fights to free Etheria from the Evil Horde which has enslaved most of this, and other, worlds. She helps the Great Rebellion, who also struggle each day for the freedom or their people and planet.
He-Man and She-Ra had been out of the public eye for a time, but Mattel wanted to capitalize on their previous success. Filmation had closed, so the new series was created by Jetlag Productions.
He-Man re-appears for his third time in toon-form, now in the new millenium. Mattel decided to take him back to his original roots on Eternia with all the original, more familiar characters. Mike Young Productions (MYP), took the wheel this time around and Mattel even hired Michael Halperin to write the new series' bible (who wrote the original Series Bible for the Filmation series). This is the first cartoon to show how Prince Adam came to learn of the Sword of Power!