If you're going to use Rome+Egypt for the West, you should probably include Ancient China in Japan's history. Japan didn't suddenly emerge out of the woods in 250AD.
By the way, I wouldn't recommend including Ancient China in Japan's history: at least don fire retardant suit, because frankly that sounds like an efficient way to offend Chinese and Japanese people at the same time.
From what I've seen Japanese and Chinese get on well. It's their governments that use the other as a convenient boogeyman 1984-style.
China was the superpower of ancient Asia, exerting significant influence on neighboring regions, and exporting its writing system, as well as science and technology to neighboring regions. As a result, approximately 60% of the words found in a Japanese dictionary are of Chinese origin (this becomes closer to 20% when you weight for usage).
Informatively, the Japanese word for China is 中国, or central country.
Additionally, the nature of the Japanese writing system means that any literate Japanese speaker would recognize the symbols in 中国 (China) mean "middle" and "country", and the symbols in 漢字 (kanji) mean "China" and "character".
https://en.wikipedia.org/wiki/History_of_Japan%E2%80%93Korea...
My main point is that there's a significant difference between a civilization adopting parts of other cultures, as opposed to other civilizations suddenly forcing it upon you through conquest.
The original thread I responded to seemed to argue that Japan had no history (read: civilization) before the adoption of kanji.
I'm not suggesting having short history makes Japan inferior or anything like that. It's just a predictable consequence of living on islands across the sea from the culture center. (My own country's history is not much longer, after all.)