Lady Macbeth of the play Macbeth has often been seen as one of Shakespeare's strongest women; in fact, some may see her as an early feminist. Why?
Consider this famous speech of Lady Macbeth's. It is some of the best evidence that she held "feminist" beliefs:
Come, you spirits
That tend on mortal thoughts, unsex me here;
And fill me, from the crown to the toe, top-full
Of direst cruelty! make thick my blood,
Stop up the access and passage to remorse,
That no compunctious visitings of nature
Shake my fell purpose, nor keep peace between
The effect and it! Come to my woman's breasts,
And take my milk for gall, your murdering ministers,
Wherever in your sightless substances
You wait on nature's mischief!
Much of the feminist movement has been motivated by a desire for equality. Women wanted to be considered just as capable of men as doing every job they did - whether that be the job of voting, holding political office, or performing certain sports. Here, Lady Macbeth is specifically asking the universe to "unsex" her. She wants her womanly characteristics taken away so that she can perform the duties that society says is a "man's job".
Lady Macbeth is strong in the beginning of the play. She is the one (Act 1, sc. 5) who is determined that Duncan should die so that her husband can become king. To convince Macbeth who vacillates about whether or not to kill Duncan, or to simply let fate take its course, she suggests that he isn't manly enough to do it (Act 1, sc. 7). Macbeth even tells her she is masculine toward the end of that scene. As the play continues, however, she becomes weaker until in Act 5, sc. 1, we see her as a sleep-walking, sleep-talking mad woman who ultimately takes her own life rather than live with the guilt of her deeds. I'm not sure I'd call her strength early on an example of feminism or simply an example of unlimited ambition.