Leontes is the King of Sicily. We do not know what he is like in ordinary times, for he is struck by an almost insane fit of jealousy soon after the play begins.
One thing we do know is that he wooed Hermione for a full three months before convincing her to marry him. His fit grows worse as time goes on, from the suspicion that Hermione is cheating on him with his childhood friend Polixenes to a conviction that he is right. He finds tiny clues that he invests with the force of truth, to the extent that he commands Camillo to murder Polixenes. When Camillo instead tells Polixenes and flees with him, Leontes is convinced that this is even more evidence against Hermione. He rages at his most faithful lords for pleading on Hermione’s behalf, his words and accusations growing wilder at each step, accusing them of being traitors, threatening to have Paulina burnt for advocating for Hermione, and sending Antigonus to abandon the new-born child in the wilderness on peril of his life. He swears that he will treat the Queen fairly, holding an open trial and sending to Apollo’s oracle at Delphi for divine sanction. He has the Queen thrust into prison and has her brought to trial before she is fully recovered from giving birth. He has announcements proclaiming her guilt posted throughout his kingdom before the trial begins, and institutes himself both prosecutor and judge in her case, telling her to expect nothing less than death as a sentence. When the oracle is read out and proves to be in Hermione’s favor, Leontes’s madness hits its highest point as he blasphemes the gods, denying the oracle’s truth. Immediately, he receives news of his son’s death, and suddenly sees himself clearly. He swears to make up for what he has done, only to be told that Hermione has died. His sense of guilt is such that he begs Paulina to berate him more, and swears to let the world know of his fault and to visit Hermione’s tomb once a day for the rest of his life.
For sixteen years he remains sunk in this depression, doing endless penance, to the extent that his lords beg him to forgive himself, and to marry again. Leontes keeps Paulina by him to keep him from forgetting what he has done, and swears not to marry again without her consent. He is somewhat revived when Florizel arrives, to the extent that he casts an appraising look at Perdita, but Paulina nixes that tendency in the bud. This is just as well, since it soon turns out that the girl is his daughter. On viewing the statue of Hermione, he is so struck by its verisimilitude that he wishes to spend twenty years looking at it, and to kiss it. He absolves Paulina of any charge of witchcraft if she will make the statue move, as promised. He is almost speechless when Hermione returns to life. Still, he is observant enough to have noted that Camillo is in love with Paulina, and he gives them to each other in marriage.