What is the history behind how date is read?

I was trying to find out if there were reading guidelines for dates, e.g., for broadcasting or competitive recitation. There seem to be a few different accepted ways of reading out dates, e.g., 1, or 2; and they don't correlate with how date is written.

For example, even though the UK writes dates as DD-MM-YYYY, BrE speakers usually read 01-Sept the same way that speakers of AmE do:

• September the first
• September first

Shortening the archaic on the thirty-first day of the month of October in the year two thousand and nineteen of the Common Era to the thirty-first of October twenty-nineteen follows somewhat naturally (by dropping redundant information).

However, what is the historical context behind the practice of reading month first, especially without dropping "the" or adding an apostrophe, like "September's first"?

The American dating convention of MM-DD-YYYY follows the older UK convention. UK speech often still follows the older convention of MM-DD-YYYY, which is why you still hear September 3 and not 3 September, although UK writing follows the modern convention of DD-MM-YYYY. See https://en.wikipedia.org/wiki/Date_and_time_notation_in_the_United_States and https://en.wikipedia.org/wiki/Date_and_time_notation_in_the_United_Kingdom