Cassandra
Cyclopedia of Biblical, Theological and Ecclesiastical Literature [1]
in Greek legend, was the most unfortunate of all the daughters of Priam and Hecuba. Apollo loved her, and promised, if she would favor him, he would teach her to look into the future. She promised, but, after having been gifted by the god, she did not keep her word. Therefore he deprived her of the faith of the people, and caused her to be a mockery among men. She was now thought insane, and, as she prophesied nothing but evil, she was imprisoned in a. tower. Later she became a priestess of Minerva, out of whose temple Ajax, son of Oileus, dragged her by the hair, when she had accidentally thrown down the statue of the goddess. At the conquest of the city she was given to Agamemnon, who took her with him on his ships, and by her became father of the twin sons Teledamus and Pelops. When the king returned to his country he was murdered, with Cassandra. Her two sons also were slaughtered by the revengeful Clytemnestra on the grave of Agamemnon. Patusanias relates that in the ruins of Mycenae there might be seen the grave of Agatnemnon, of Cassandra, and of the two sons. She had a temple at Leuctra and a statue by the name of Alexandra.
The Nuttall Encyclopedia [2]
A beautiful Trojan princess, daughter of Priam and Hecuba, whom Apollo endowed with the gift of prophecy, but, as she had rejected his suit, doomed to utter prophecies which no one would believe, as happened with her warnings of the fate and the fall of Troy, which were treated by her countrymen as the ravings of a lunatic; her name is applied to any one who entertains gloomy forebodings.