Paul, first of all, the fifth letter of the word is not a "B". The fifth letter is the German character called "scharfes S" and is written thus: ß
The character "ß" is used in many (but by no means all) German words to represent "ss". So this particular word could also be correctly written as "Preussen".
PREUSSEN (pronounced: PROYS-en) is simply the German name for PRUSSIA.
The former German state of Prussia was Germany's largest state by far, covering an area roughly equivalent to that covered by the U.S. states of New York, Vermont, Pennsylvania, New Jersey, Maryland, and Delaware combined. Prussia's capital was Berlin, which, from 1871 on, was also the capital of Germany as a whole.
Following World War II, the vast state of Prussia was broken up and in 1947, the Allies declared the state of Prussia officially abolished.
Here is a map of Germany as it was from its unification under Bismarck in 1871 until 1918. You will see Germany's states, including Prussia and it provinces. You will note how vast Prussia was. It extended from East Prussia in the northeast, all the way to and including the Rhineland in the west. That's a distance of more than 800 miles!http://www.rootsweb.com/~wggerman/map/germanempire.htm
Before you can think about church records, you of course first have to find out which city, town or village in vast Prussia your great-grandfather was from. If for starters, you could at least determine which Prussian province he was from, that would narrow things down a little bit anyway.