Rosalind begins the story as a dependent of the court, but when she is banished she must use her wits and inner strength to fend for herself. She disguises herself as Ganymede to make her way in the world. This disguise allows her greater freedom of speech and action. Even when she falls in love with Orlando, Rosalind keeps her head on her shoulders and tests to see whether his love is true or just a passing fancy. Through her courage and cleverness (and a bit of good luck), Rosalind is able to turn her fortunes around: she marries Orlando and returns to court.
Orlando is at the end of his rope at the story's outset; he has no hope of life as a gentleman under his devious brother's thumb. When he tries to prove his worth in a wrestling match, he earns more enmity than accolades and is forced to flee to safety in the forest. Through his trials there he proves his bravery, loyalty, and honor, and earns the hand of his true love, Rosalind.
At first Celia is wrapped up in her friendship with her cousin Rosalind. When Rosalind falls in love and turns her attention to Orlando, it is a rude awakening for Celia, who tries to dissuade her from the match. In the end she becomes engaged to Oliver, the son of Sir Rowland de Boys and brother of Orlando.
Touchstone loves being himself. He revels in his position at court, his cleverness, and his worldly cynicism. Although his lifestyle changes when he goes with Rosalind and Celia into the forest, his attitude doesn't, until he meets Audrey. At first he just wants to bed her, but this notion soon gives way to honorable marriage as he sees both its inevitability and the benefits it can offer.
Duke Frederick is all about power and money and easily ruins the lives of others in order to further his own position. His sudden conversion into a man of religion is unexpected but shows a complete turnaround in his character. Power and money mean nothing to him as a convert, and he tries to make amends for past wrongs by transferring his former wealth and power back to Duke Senior and his loyal followers.
Duke Senior's sturdy character doesn't change much even as his circumstances shift throughout the play. During his exile he looks for the bright side of his situation, and when his fortunes are restored he doesn't take forest life for granted and rush right back to the court. He enjoys every moment and serves as a model of loyal, loving leadership.
Oliver, despite having all the wealth and power in the family, is jealous of his youngest brother Orlando for his virtues and popularity. He treats him abominably, withholding education and opportunity from Orlando. He even plots to kill him. When Duke Frederick confiscates his lands, though, Oliver suffers in the forest and faces his own mortality when threatened by wild animals. When Orlando saves his life, Oliver sees what a villain he has been, and they reconcile. Good luck smiles upon Oliver, too, when he meets and falls in love with Celia. In the end he decides to remain in the forest, living a simple life with his love.