Wasn't Ruby invented in Japan?
I hear the weeaboos across the world now screaming “what about Ruby!”, but Ruby just proves the point. A Mormon Japanese dude (read: English literate, world-focused, non-Otaku, non-loner mindset) coupled with an excellent framework that gained fame world-wide (Rails). It’s nice that there are great Japanese Rubyists but they are not responsible for the popularity of the language.
The Japanese in question is this guy: http://en.wikipedia.org/wiki/Yukihiro_Matsumoto .
With all the Ruby enthusiasts outside of Japan, it seems unnatural that most of the core commiters are still Japanese.
A few years ago Cookpad (http://cookpad.com/), a Japanese recipe site with millions of users, switched to Rails. That may be contributing to a change in awareness locally.