When Major Carol Danvers meets Dr. Walter Lawson (Captain Mar-Velll), she doesn't know this is the beginning of a major change on her life. Caught in an explosion together, Mar-Vell (who is really in alien with super powers) manages to save Danver's life, albeit sustaining serious injuries.
In a landmark moment for equality in comics, "Ms. Marvel" #1 is published 1977, and is lauded as progressive, beyond it time. On top of her superhero duties, she also fights for equal pay for equal work in her civilian identity. Naturally, she is then kidnapped by a time traveler from the future named Marcus, who brainwashes and impregnates her.
She then becomes alcoholic, and is suspended from the Avengers in disgrace.
Eventually she returns to Avengers duty, until Secret Invasion - when Norman Osborne (Super Villain Green Goblin), becomes the leader of the Avengers, at which point she walks out and joins the New Avengers, with Osborne recruiting fellow villain, Karla Sofen (Moonstone) to be the new Ms Marvel. Osborne then causes Danvers powers to overload causing her death. After pledging to defend the human race, Sofen is then accepted as Ms Marvel, which no-one else seems to have a problem with.