Given that so many (all?) other English speaking nations including the UK usually speak it the other way around and write it day-month-year, I wonder if writing (especially thinking about newspapers here) influenced the way you speak it and not the other way around. March 1st saves space and ink over 1st of March or some other rationale. Someone certainly has already investigated the origin of putting the month first?

Edit: [1] says my hypothesis is most likely wrong, but that the UK just changed it later to match the rest of Europe. So maybe that influenced their way of speaking? In any case, matching the way one speaks doesn't seem to be a strong reason as it's easily adaptable and month names are unambiguous. Interestingly it also quotes that using a purely numeric format is incorrect in any formal use as to not confuse month and day.

[1] https://iso.mit.edu/americanisms/date-format-in-the-united-s...