"You remember Eponina, who kept her husband alive in an underground cavern so devotedly and heroically? The force of character she showed in keeping up his spirits would have been used to hide a lover from her husband if they had been living quietly in Rome. Strong characters need strong nourishment." [Stendhal, "De l'Amour" 1822]Sense of "person in a play or novel" is first attested 1660s, in reference to the "defining qualities" he or she is given by the author. The Latin ch- spelling was restored 1500s.
character char·ac·ter (kār'ək-tər)
An attribute, trait, or distinct structural or functional feature. Also called characteristic.