Historical Thoughts on Relationship Between Japanese and Korean
I know that *today* it's a popular theory that the Japanese and Korean languages are related or were in extended close contact at some point in the past. I also know that the Yamato Japanese have presumably always known that their Yayoi ancestors came to the Japanese islands from the Korean Peninsula. What I'm not aware of is the historical thoughts on the relationship between the languages.
To my knowledge, scientific analysis of a potential relationship between Japanese in Korean began in the mid to late 1800s in the early days of scientific linguistics. What did Japanese and Korean scholars think about the relationship between their languages before then? Did they see them as being related in any way before then? Did they take note of words that were similar in their languages that they couldn't find a Chinese equivalent to? Did they have any ideas about how their languages related to the *other* languages of East Asia?