Word hunter Ben Zimmer reports the earliest sighting so far of “the elusive first Ms.” The word, an alternative to the marriage-specific titles Miss and Mrs, turns out to be over 100 years old. (An earlier example of Ms from 1767 [see images below] is probably an abbreviation of Miss, not the marriage-neutral, innovative Ms. that Zimmer’s been looking for.)

Not the oldest Ms? The tombstone of “Ms” Sarah Spooner, who died in 1767 in Plymouth, Massachusetts. Rendered by the stonecutter as “M” with a superscript “S” (see detail below), this is almost certainly an abbreviation of Miss or Mistress, not an example of colonial feminism or a slip of the chisel, as some have suggested.

Look closely to see the “S” carved above the “M” in this detail of “Ms.” Sarah Spooner’s headstone
Zimmer didn’t need carbon dating to determine that the article about Ms. appeared on Nov. 10, 1901, under the heading “Men, Women and Affairs” in the Springfield (Massachusetts) Sunday Republican (page 4, below the fold), and it recommended Ms. as a term to be used when you don’t know a woman’s marital status.
Today we tend to think of Ms. as coming out of the women’s movement of the 1970s, a marriage-neutral term for women that paralleled the men’s term, Mr., and that succeeded despite the howls of derision from (mostly male) language guardians.
But this 1901 use of Ms. as a new, intentionally ambiguous abbreviation for both Miss and Mrs., not a simple replacement for Miss, comes not from feminism but from more conservative “manners” advice which counseled that it might be insulting to address a married woman as “Miss” or a single one as “Mrs.”
The author of the Republican article writes (perhaps patronizingly, in the florid journalistic style of the day) that Ms. “does homage to the sex without expressing any views as to their domestic situation,” adding that the new form is eminently practical: “The abbreviation ‘Ms.’ is simple, it is easy to write, and the person concerned can translate it properly according to circumstances.” According to him (the author of the piece was probably a man), a married woman will read it as “Mrs.,” while a single one will interpret the word as “Miss.”
As for the form of Ms., we’re told, “What could be simpler or more logical than the retention of what the two doubtful words [i.e., Miss and Mrs.] have in common,” that is, the letters “M” and “S.” The author even provides Ms. with a pronunciation, “Mizz,” calling it “a close parallel to the practice long universal in many bucolic regions, where a slurred Mis’ does duty for Miss and Mrs. alike” (presumably, “bucolic” refers to rural areas and the South).

Excerpt from the Springfield Republican article on Ms., as reprinted a week later in the Salt Lake City Daily Tribune, Nov. 17, 1901, p. 21. Image courtesy of Fred Shapiro, editor of the Yale Book of Quotations.
It’s also possible that despite this early example, Ms. comes out of 1900s progressive politics and feminism rather than “Miss Manners”-style etiquette advice. At a feminist rally in 1914, the suffragist Fola La Follette recommended Miss as a general title for women both before and after marriage. Although La Follette gives no abbreviated form, Ms. may turn out to be a shortening of this feminist repurposing of Miss after all. And as such it would have been pronounced “Miss,” except by speakers of more “bucolic” dialects of English.
Zimmer’s “elusive Ms.” resurfaces again in 1932, when M. J. Birshtein writes to the New York Times to ask whether “when addressing by letter a woman whose marital status is in doubt,” one should write “M’s” or “Miss.” Birshtein is concerned that M’s, as he writes it, is too similar to “Miss,” and he asks whether “it is too indefinite and that if it is used before the name of a single woman, it makes her extremely conscious of her ‘bachelor girl’ state and thus creates within her a real feeling of antagonism.” Birshtein’s concern would seem to make sense only if M’s was pronounced “Miss.” Unfortunately, the Times didn’t print any answers that it might have received to Birshtein’s question.

M. J. Birshtein, “ ‘Miss’ or ‘M’s’?” letter to the New York Times, May 29, 1932, p. E2. Birshtein, who sees Miss and M’s as alternatives, worries that M’s may be insulting to single women.
Ms. resurfaced briefly in 1949, in Mario Pei’s influential book The Story of Language (Pei advises his readers to pronounce it “Miss”), and again in the 1950s, when Ms. enjoyed a brief vogue in business writing textbooks. But it doesn’t really make much of a splash till the 1970s – Ms. Magazine began publishing in 1971 – though the stylistically conservative New York Times didn’t O.K. the form as “fit to print” until 1986.
Whatever the origins of Ms., the meaning of the title today has shifted. Despite its association with 1970s feminism and the fact that style guides recommend it as a marriage-neutral option, and despite the fact that many women today use the title in the way it was initially envisioned, there are also many women, perhaps a majority, who use Ms. as a trendy alternative to Miss rather than a replacement for the “Miss/Mrs.” options. (Even twenty years ago, the unmarried women teachers of my children’s public school were listed in the staff directory as “Ms.,” while the married ones were “Mrs.”) Or they associate Ms. with the unmarried women, the widows and divorcées, of their mothers’ generation.
Words often break free from their original sense and come to mean instead what people want them to mean. Titles in English are particularly unstable. In the past, Miss was often adopted by married women; Miss was used as well to refer to young women, even married ones; and Mrs. served as a term of respect for older women, married or not. Titles reflect social structure and they change along with changing social roles, so it shouldn’t surprise us if some people use Ms. to signal their feminism while others use the same term to reinforce the traditional gender roles that Ms. may have been coined to subvert.
On the other hand, if Ms. came into existence simply because letter writers feared insulting women who embraced traditional gender roles, then it looks like the once conservative though rarely-used abbreviation was radicalized as well as popularized by the 1970s women’s movement. The present status of the word as feminist for some, traditionalist for others, suggests that the radical status of Ms. may have eroded, and that while some women prefer the marriage-neutral term, others are keen on preserving the unmarried/married distinction.