How Long has She Been Ms.ing?

I recently read a wonderful book which took place in the 1920s. In it, a character referred to a "Ms. McMein." The use of the term, "Ms." in this book set my ocasionally well-oiled memory gears in motion and I recalled that the honorific did not really come into use until the early 1970s.
There was a proposal in 1901, in the Sunday Republican of Springfield, Mass., to use the title in order to avoid any confusion between Miss and Mrs. but after causing a minor uproar for a few weeks, the proposal was soon forgotten.
The proposal briefly resurfaced in 1932 when a letter writer in the New York Times wondered if "a woman whose marital status is in doubt" should be addressed as Ms or Miss.
In 1949, the philologist, Mario Pei noted in his book "The Story of Language" that "feminists who object to the distinction between Mrs. and Miss and its concomitant revelatory features, have often proposed that the two present-day titles be merged into a single one, 'Miss' (to be written 'Ms.')."
Nothing more was heard until1961 when Sheila Michaels, a 22 year-old civil rights worker in New York City, took up the fight for "Ms." Fiercely independent, Michaels loathed having her identity defined by her marital status and she became a tireless lobbyist for the title as a feminist alternative to "Miss" and "Mrs."
For several years there was little interest. The turning point came in 1969 or 1970 when Michaels was interviewed on the progressive NYC radio station WBAI. The program, "Womankind," invited her on with other members of a group known simply as "the Feminists." During a lull in the show she made an impassioned plea for the use of Ms. The following August, days before a national demonstration by women's rights supporters celebrating the 50th anniversary of suffrage, Gloria Steinem registered her approval in New York magazine and Ms. became recognized as the calling card of of the feminist movement. The rest, as they say, is history.
Oh, by the way, the wonderful book in which I noticed that harmless little anachronism was "Murder Your Darling: an Algonquin Round Table Mystery," by J.J. Murphy. I recommend that you read the book at your earliest convenience.