The Yellow Martians, or Okar, are a humanoid race, depicted in the "Barsoom" series. They were created by Edgar Rice Burrougs (1875-1950). They are an insular race, inhabiting the frozen northern (arctic) regions of Mars. Their cities, like Marentina and Kadabra, are protected from the harsh weather conditions by the glass domes surrounding them. When exiting their cities, the Okar brave the elements equipped with fur clothes and boots.
Reportedly they were once counted among the dominant races of their planet. But they were unable to face the growing population of Green Martians. The latter attacked them in formidable hordes and managed to conquer most of the areas once ruled by the Okar. The remnants of the proud Okar retreated towards the frozen North. Using the rough terrain to discourage those enemies foolhardy enough to follow them.