Thuvia is a princess, the daughter of Thuvan Dihn, the Jeddak of Ptarth. For a long time, she pined for Prince Carthoris of Helium, but had been promised to Kulan Tith, the Jeddak of Kaol. This conflict between her sense of duty and her heart led to the events of Thuvia, Maid of Mars.
History
Enslavement
The only daughter of Jeddak Thuvan Dihn of Ptarth, Thuvia was promised to the much older Jeddak Kulan Tith of Kaol. She apparently disliked the prospect of this marriage so greatly that she set off on a pilgrimage for the Valley Dor, the Martian equivalent of Heaven, knowing that her father wouldn't dare try to bring her back (as anyone who returned from the valley was believed to be cursed.) The princess had hoped to find a blissful new life in paradise, but instead she was enslaved by the monstrous therns. For fifteen years, Thuvia was subjected to the sort of indignities which could not be ennumerated in polite conversation in the early 20th century.
Thuvia posing with a banth (Michael Whelan)
Thuvia was a smart, resourceful girl, however, and soon found a means of escape by studying the techniques that the therns used in order to control banths, the fearsome Martian equivalent of lions.