THANK THE GODDESSES FOR HYRULE HISTORIA THE ZELDA TIMELINE THEORIES. NEVER AGAIN OH GOSH.
Um, besides the connections stated between Gen. I and Gen. II, and the Gen. V games, there are some big hints that DPPt happens at the same time as Gen. II events, three years after Gen. I events. (And possibly the RSE events as well, but that has been summed up as ambiguous placement because Pokemon logic.)
Yes that is the exact area I'm talking about, kinda dessert like with creepy white sky towers of UFO technology... LOOKS LIKE ORRE TO ME.
Actually, I went back and watched the trailer again, taking a closer look and it seems like the region is based off of Europe, so there might be some history about everything Pokemon in general.