Amn’t —-where it occurs in US

Solution 1:

In modern usage, amn't as primarily Scottish and Irish, but according to the OED, it appears to have been more widespread in the past, falling out of use as shifts in vowel patterns made it more difficult to pronounce than an't or ain't. The OED lists a number of forms of am with a negative particle, many remaining in current dialectical use. To focus on the amt / amn't variants, these include the following, along with the centuries they have been known to be in use:

• 16 amt
• 16–17 (19– U.S. (nonstandard)) amn't
• English regional (west midlands and northern)
  • 18 ammot (Yorkshire)
  • 18– amma (Shropshire)
  • 18– ammad (Shropshire)
  • 18– amna
  • 18– amnad (Shropshire)
  • 18– amn't
  • 18– am't
  • 19– amment
  • 19– ammet
  • 19– amno (north-west midlands)
• Scottish 18 amnin
  • 18 ym-n'
  • 19– amna
  • 19– amnae
  • 19– amn't
• Irish English
  • 18 am'n't
  • 18 imin't (northern)
  • 19– amnae (northern)
  • 19– amn't.

(For some background on why aren't supplanted amn't, an't, and ain't in standard English, see Why "ain't I" and "aren't I" instead of "amn't I"?).

The U.S. experienced mass immigration of Irish in the 19th century, including around a million and a half Scotch-Irish (i.e. Ulster Scots) who settled in large numbers in Virginia and the Carolinas. It may very well be that your family preserved this usage for several generations after immigration, and that others did as well in their community, at least enough that it was not seen as unusual.

Solution 2:

I grew up in northwest Louisiana, and we used "amn't I" all of the time! I am descended on both sides from Scotch-Irish who came through North Carolina in the early 19th century. Uniquely, my maternal grandmother grew up in the Ozark Mountain region of north Arkansas. We used "amn't I" without a second thought - period. It was an easy, natural, and fluid way of asking a question - "amn't I coming with you?" or "amn't I going to get some pie?"

We moved to New Orleans in 1970, and I never heard the beautiful phrase again. Interestingly, during the '60s in North Louisiana, the use of "amn't I" went beyond just our immediate family. The only other place I heard it was from a family in Connecticut. The speaker would have been fortyish in 1967. I welcome any anecdotes about this beautiful and forgotten contraction - amn't I encouraged by others to start a foundation to reintroduce its use?