Mann Co. has managed to build an entire mining town on the side of the Ben Nevis (behind it, so that the tourists can't see). RED has control of the mines currently, but BLU is looking to nab some of that sweet, sweet scottonium (a metal that allows Scots to inflict guaranteed critical hits on the English) for themselves.

Why does either team want to decimate the English? Who knows, maybe their CEOs are part English.