A friend sent me a link to Google Books Ngram Viewer. You can look up words, in various languages, and see how frequently those words showed up in books, during a specific time frame.
For example, I looked up Psychiatry, Psychoanalysis, Freud, CBT, ambivalence, Ego, and Id, and it came out like this:
I looked these up in English, but there are language variations you can use, such as British English and American English, and other languages. There's even an English Fiction category.
I thought it was a bit strange that there were spikes in both "Ego" and "Id" in the early 1800's, while Freud was born in 1856.
I checked Oxford Dictionaries Online, and Ego's origin was listed as early 19th century, from Latin, literally, "I". Freud used the German word, "Ich", which also means "I".
Id's origin was listed as:
1920s: from Latin, literally 'that', translating German es. The term was first used in this sense by Freud, following use in a similar sense by his contemporary, Georg Groddeck.
So I don't know where the early 1800's spike came from. I'll have to check my trusty OED, if I can find the magnifying glass that came with it.
I threw "ambivalence" into the mix because I was pretty sure it was coined by, or at least used very early on, by Freud. Since it first appears around 1910, that may be correct. Looks like another job for the OED.