In choosing a capital for the Federal Republic of Germany after World War II, Frankfurt was in many respects the logical choice. Economically, it was a major center of commerce, transportation, and manufacturing. Politically, it had been the place where Holy Roman Emperors had been elected, and was the site of the assembly which tried to unify Germany in 1848; more recently, it had been the seat of "Bizonia," the merger of the American and British occupation zones. Culturally, it was the birthplace of Goethe (though of course Bonn had Beethoven). In fact, maybe Frankfurt was *too* logical a choice; choosing it would seem to indicate that the Federal Republic as a West German state was considered permanent. Bonn seemed more obviously a "provisional" capital. (Note that the Federal Republic's constitution was called a "Basic Law" rather than a constitution, and stated that it would cease to have effect when the entire German people could adopt a new constitution.) Of course, another (maybe the main?) reason Bonn was chosen was stated very simply by Lucius Clay: "Frankfurt was so logical...except that Mr. Adenauer loved the Rhine. Period." http://books.google.com/books?id=5HVmAgAAQBAJ&pg=PA409
Had Frankfurt been chosen, the only historical effect I can think of is that it is uncertain (though still likely) that the capital would have been moved to Berlin after reunification. The vote in the Bundestag on moving the capital to Berlin was a fairly close one: http://en.wikipedia.org/wiki/Decision_on_the_Capital_of_Germany I am not sure, had the issue been one of moving the capital from Frankfurt to Berlin, it would have carried. (BTW, Willy Brandt caused some controversy during the debate by saying that after France had been liberated it would have been unthinkable to keep Vichy as the capital...)
Had Frankfurt been chosen, the only historical effect I can think of is that it is uncertain (though still likely) that the capital would have been moved to Berlin after reunification. The vote in the Bundestag on moving the capital to Berlin was a fairly close one: http://en.wikipedia.org/wiki/Decision_on_the_Capital_of_Germany I am not sure, had the issue been one of moving the capital from Frankfurt to Berlin, it would have carried. (BTW, Willy Brandt caused some controversy during the debate by saying that after France had been liberated it would have been unthinkable to keep Vichy as the capital...)