Why did Otto Von Bismarck exclude Austria from the unification of Germany?
Sort of what other posters have said already—Austria was part of Austria-Hungary at the time, an empire which included not just current-day Hungary but Czechoslovakia, Slovenia, Serbia, and so on—it would have been a nightmare, practically speaking, for Prussia/Germany to try to absorb those other countries into itself (nor would it have made any sense, or had good long-term chances of surviving intact). Theoretically I suppose he could he broken up Austria-Hungary and tried to incorporate Austria only, but this was probably way beyond his strategic interests at the time (he was presumably already planning on fighting a war against France shortly thereafter, a much tougher opponent than either Denmark or Austria).
