There are three categories for Europe under localities - Western Europe, Central Europe and Eastern Europe. Germany is in Central Europe because that is where it is, it is not considered part of Western Europe - Poland is also Central Europe, because it is also in Central Europe, neither Western nor Eastern Europe. I would suggest you read up a bit of the history of Westfalen and you will find that it was a somewhat vague region and part of Prussia, so you would probably get most help from the board for Prussia under Historical Regions. Since 1947 the only "Westphalen" has been the "Land" (Province) of NordRhein-Westphalen which became a "Land" in the Federal Republic and is still a "Land" in re-united Germany. Some methodical searching will answer most of the questions.