Hi Kiya,
That's pretty interesting. I would guess that it has been around for a very long time, but people did not know what was going on too.
My son has bipolar. I was very clueless to be honest. I had never heard of it, didn't know anything about mental illness. When he was almost 15, our world exploded in a sense. Looking back I now see so many things that should have alerted me. I knew something was going on, but I didn't know what mental illness was. All this while myself having DID. I had no clue. I didn't know what was normal, what wasn't. I'm so glad more things are going on to make more people aware of mental illnesses. If I had only known a lot of things way back then, my life and the lives of my children would have been heaps different.
It's interesting to see when things were first documented. Amazing that we are just now becoming kind of aware as a people.
If you find that post, please bump it up. I'd be very interested in reading it too. You can also do an advanced search and select the DD forum to narrow down the search.

Thanks Kiya.