The first ‘Ladies’ Day’ in major league history took place on June 16, 1883 when the New York Gothams (later known as the Giants) offered free admission to all women, both escorted and un-escorted, at the Polo Grounds. The lucky ladies had the opportunity to watch their Gothams defeat the Cleveland Spiders, 5-2.
This article states that Ladies Day originated in NY in 1893, but there are literally hundreds of mentions of Ladies Days in baseball from the 1880s, and even the 1870s! Advertisements in newspapers for this promotion are easy to find in old newspapers. Not to mention Ladies Days held in other sports like horse racing and boxing, also earlier than the 1890s.
It’s almost impossible to nail down “firsts” in baseball and other sports, but this date of 1893 is way off.
You are correct that 1893 is off — I double checked the date in the post and it should have been 1883. I have fixed the typo.
Could you share where you are seeing 1870s? I can’t seem to find any mention of it that early, but I am curious.