Rails was around before December 2005; that was just the release date for version 1.0. I know I had a personal site running on pre-1.0 Rails in early 2005. But

Rails was around before December 2005; that was just the release date for version 1.0. I know I had a personal site running on pre-1.0 Rails in early 2005. But your general point stands, Rails and Django grew up together and cribbed from each other liberally. The biggest example would perhaps be the merging of Merb into Rails 3, where Merb was a competing Ruby framework that had a much more Django-like vibe. These fanboy arguments don't hold much weight these days. They each do their own thing, they each borrow the best from each other, and everyone benefits.