Anschluß (Anschluss), common term for efforts to unite Austria with Germany and for the actual annexation of Austria in March 1938. The basis for the striving for annexation was found in the centuries-old links within the Holy Roman Empire, which was wrongly seen as being tantamount to a German national state, in the position of the Habsburgs as "Roman-German" emperors up to the abdication of the imperial title in 1806, and in the Austrian presidency of the German Federation founded in 1815. The growing hegemonical struggle with Prussia Germany - Austria resulted in the conflict, at the Frankfurt National Assembly of 1848/49, between the "Great Germans" (Grossdeutsche), who pleaded for integration of the Austrian empire and the Slavic areas into the planned national state, and the "Little Germans" (Kleindeutsche), who favoured the unification of Germany under Prussian leadership without the inclusion of Austria. The exclusion of Austria from the German unification movement became reality with Austria's defeat in the Austro - Prussian War of 1866 and the establishment of the German Reich in 1871.
In the second half of the 19th century Pan-German groups and parties established themselves in Austria (particularly under G. von Schönerer); they called for the dissolution of the Austro-Hungarian Monarchy and the union of the German-speaking parts of Austria and Hungary with the German Reich. The anschluss movement became politically important when the Austro-Hungarian Monarchy disintegrated and the successor states were established in 1918, since few people believed in the viability of the residual parts of Austria. On November 12, 1918, the National Assembly of German-Austria declared that Austria was part of the German Republic, and a second declaration to that effect, largely inspired by O. Bauer, was made on March 12, 1919. Article 88 of the peace treaty of Saint-Germain then stipulated that Austria was forbidden to join Germany without the express consent of the League of Nations. With financial support from Germany, plebiscites were held in Tirol in April 1921 (145,302 votes for, 1,805 against union with Germany) and in Salzburg in May 1921 (98.546 for, 877 against) but international pressure prevented any further plebiscites. In 1922 Austria waived its claim to union with Germany in the Geneva Protocol. However, the anschluss movement continued to play an important role in Austrian economic, domestic and cultural politics. Great Germans, Social Democrats and some Christian Socialists still favoured anschluss, and many private associations, mostly financed by Germany, were formed (such as the "Österreichisch-deutscher Volksbund, the "Österreichisch-deutsche Arbeitsgemeinschaft", the "Deutscher Klub" and the "Deutsche Gemeinschaft"). Throughout this period Austrian policy-makers clearly pursued policies aiming at harmonisation and assimilation. A customs union between Germany and Austria was agreed upon on March 19, 1931 but interdicted by the International Court of Justice in The Hague. In July 1932 Austria signed the Lausanne Protocol, in which it reiterated its waiver of the right to establish a union with Germany.
As Hitler ascended to power in Germany in 1933, calls for anschluss within Germany became louder. They were, however, for the most part based on the old conceptions of German imperialism and the Weimar Republic. A pro-German policy on the part of Austria was sought to be achieved by an economic boycott, terror and political pressure were brought to bear on Austria to force the Dollfuß government to adopt pro-German policies. The anschluss was promoted in Austria by the NSDAP (National Socialist German Workers Party), which gradually absorbed virtually all members of the nationalist camp, while the Social Democrats and Christian Socialists abandoned their claims for union with Germany. When the NSDAP was banned in Austria and Chancellor Dollfuß was assassinated in July 1934 by a Nazi contingent including many Germans, efforts to press for union with Germany came to a standstill. The July 1936 agreement between Germany and Austria and the policy of the "Deutscher Weg" (German Way) failed to achieve normality and actually resulted in Austria's independence being increasingly undermined economically, politically and militarily. When an gradual development of pro-anschluss sentiment appeared impracticable, Germany intensified its pressure for union from the summer of 1937 onwards, which finally resulted in the invasion of Austria by German troops on March 12, 1938 and, one day later, the implementation of anschluss or annexation by the Law on the Reunification of Austrian with the German Reich Austria 1938-1945.
On the basis of the Moscow Declaration of 1943, the effects of the war and the fact that Austrians had by and large abandoned all ideas favouring anschluss, the Declaration of Independence of April 27, 1945 declared the union with Germany null and void. The prohibition of union with Germany was reiterated in Article 4 of the Austrian State Treaty of 1955.