Austria, though a leading German state in 1815, disliked the idea of a united Germany since it would put her in a very embarrassing position. Although the Habsburg was of German origin, Austria was reluctant to become part of a united Germany because it would oblige her to give up her vast non-German population and territories in the Austrian Empire. What is more, she even opposed the idea of a united Germany since it would create a strong neighbor next to her. This was by no means desirable for Austria politically or strategically. Besides, the success of German Unification might lead to the disintegration of the Austrian Empire since it would stimulate the independence movements among those national minorities living under Austrian rule. Therefore, the multi-national nature of the Austrian Empire had dictated the policy of Austria towards the movements of German Unification.
Apart from this, the weaknesses of Austria and the conservatism of her statesmen also explained why she Congress of Vienna, Austria had been very much weakened by financial and racial problems within her empire. On the other hand, the conservative Austrian leaders also detested the ideas of nationalism and changes. All they would like to do was to maintain the status quo. As a result, the unification of Germany, which might cause so much trouble and danger to the Austrian Empire, had to be suppressed bluntly.
As a result of these considerations, Austria had made a series of attempts to suppress German Unification after 1815. Student movements were suppressed in late 1810s and the Carlsbad Decrees were passed to check the growth of nationalism in Germany. Besides, she also took the lead in suppressing the German revolutions in 1830 and 1848. Metternich also attempted to check the growth of nationalism in Germany and Europe by making use of the Congress System. In fact, Austria would even risk a war to prevent the success of German Unification. In 1849, when the Frankfurt Parliament...