Princess Katharine (976-?) was born to Prince Malcolm and Princess Elena of Castle Wyvern. Her mother died before she was seven, and she was mostly raised by her father. She grew up with a xenophobic hatred towards the gargoyles of Wyvern, and after her father died and she ascended to Wyvern's throne, she openly showed her disdain and scorn for the gargoyles. This may have encouraged others of Castle Wyvern, such as her advisor the Magus, to adopt her anti-gargoyle stance.
In 994, when Katharine was 18, her disdain for the gargoyles helped lead to Wyvern's Captain of the Guard and the Wyvern clan's second-in-command, Demona, betraying the castle to a party of Vikings led by Hakon. The Princess was held prisoner by the Viking leader, and the Captain suggested they ransom her to her uncle, King Kenneth. When Goliath and the other six survivors of the Wyvern Clan attacked the Viking camp, Hakon and the Captain ran away with the Princess, which led the Magus to believe she was now dead. In actuality, Katharine nearly fell off the cliff where Goliath had cornered Hakon and the Captain, but she was saved by the gargoyle leader. When she returned, and saw the Magus's grief-madness-induced handiwork- five of the six surviving gargoyles trapped in stone sleep- and was shocked. Before Goliath had himself trapped in stone sleep with them, she swore to protect the eggs of the Wyvern clan's rookery.
She, along with the Magus, Tom, Mary, and the eggs, travelled to the lands of her uncle Kenneth. They stayed with her uncle, until he was assassinated by Constantine, one of his generals. Constantine desired the Princess to be his wife, and planned to marry her come Michaelmas in 995. Thus, she made plans to leave, and, with the help of the Magus, Tom, Mary, and Finella, she and the 36 gargoyle eggs made it to Avalon.
For the next 43 (Avalon) years, Katharine, the Magus and Tom lived an idyllic life on Avalon. Eventually, Katharine fell in love with Tom, and, after the gargoyles hatched, the two raised them like they were their own children. In 1995, the Archmage and his forces attacked Avalon, and Princess Katharine helped treat and defend the wounded members of the Avalon clan, culminating in her using Demona's own laser rifle to incapacitate the gargoyle. She grieved greatly over the Magus's death during that conflict.
She and the other inhabitants of Avalon were nearly forced out by the Lord of the Third Race, Oberon, but she helped create an iron bell which led to Oberon allowing them to remain. At present, Katharine still lives on Avalon, with Tom and the Avalon clan.