[Alberta's Child]

Professional police forces didn't crop up until around the mid-Nineteenth century.

I've made the case that professional police forces only came into existence because of the large-scale immigration (of European peasants, mostly Irish) and internal migration (of freed slaves) to cities in the Northeast. The governing classes of these cities simply decided that disorder and chaos would rule the day if the Second Amendment was applied to these people. It's no coincidence that police departments came into existence right around the same time that the first gun control laws were passed.

[George Smiley]

You're right.

Here are some suggestions that you might find to be fun:

Do a websearch for "Sullivan Laws" and "swarthy immigrants", as I believe that the law (or editorials of that time advocating its passage) used that phrase.

Check out Clayton Cramer's "The Racist Roots of Gun Control" if you haven't already. claytoncramer.org

H.L. Mencken wrote an essay around this time as well.
Do a websearch on Mencken and "gun control".

If you click on my name and go to LINKS, you'll find a lot of RKBA research listed.