Complex sentence: But the German movement and Prussia had reckoned without the European powers, which were united in opposing any dismemberment of Denmark, even Austria, like Holstein a member state of the German Confederation, refusing to assist in enforcing the German view.
Split into simpler sentences: But the German movement and Prussia had reckoned without the European powers, which were united in opposing any dismemberment of Denmark. Even Austria, like Holstein a member state of the German Confederation, refused to assist in enforcing the German view.