Complex sentence: Bismarck himself resisted the adhesion of Baden to the North German Confederation: he had no wish to give Napoleon III of France so good an excuse for intervention; but the opposition of Baden to the formation of a South German confederation made the ultimate union inevitable.
Split into simpler sentences: Bismarck himself resisted the adhesion of Baden to the North German Confederation. He had no wish to give Napoleon III of France a good excuse for intervention, but the opposition of Baden to the formation of a South German confederation made the ultimate union inevitable.