The Isle of Shador is a prison island located on the Omean Sea. The prison was built and owned by the Black Martians, who use it to detain male prisoners (female prisoners are usually made slaves or killed for food.) The earthman John Carter was detained there after he and the princess Phaidor were captured by the black pirates. Ironically, the man responsible for their capture, Dator Xodar, was himself detained there after the "living goddess" Issus learned that he had been bested in combat by Carter. It was also in Shador that Carter first met his son, the prince Carthoris of Helium, who had been born after Carter found himself returned to Earth.