German nationalism (German: Deutschnationalismus) is a political ideology and historical current in Austrian politics. It arose in the 19th century as a nationalist movement amongst the German-speaking population of the Austro-Hungarian Empire. It favours close ties with Germany, which it views as the nation-state for all ethnic Germans, and the possibility of the incorporation of Austria into a Greater Germany.

Over the course of Austrian history, from the Austrian Empire, to Austria-Hungary, and the First and the Second Austrian Republics, several political parties and groups have expressed pan-German nationalist sentiment. National liberal and pan-Germanist parties have been termed the "Third Camp" (German: Drittes Lager) of Austrian politics, as they have traditionally been ranked behind mainstream Catholic conservatives and socialists. The Freedom Party of Austria, a far-right political party with representation in the Austrian parliament, has pan-Germanist roots. After the Second World War, both pan-Germanism and the idea of political union with Germany became unpopular due to their association with Nazism, and by the rising tide of a civic Austrian national identity.

Within the context of rising ethnic nationalism during the 19th century in the territories of the multi-ethnic Austrian Empire, the "German National Movement" (German: Deutschnationale Bewegung) sought the creation of a Greater Germany, along with the implementation of anti-semitic and anti-clerical policies, in an attempt to entrench the German ethnic identity. Starting with the revolutions of 1848, many ethnic groups under imperial rule, including the Serbs, Czechs, Italians, Croats, Slovenes, and Poles, amongst others, demanded political, economic, and cultural equality. Traditionally, the German-speaking population of the Empire enjoyed societal privileges dating back to the reign of Empress Maria Theresa, and that of her son, Joseph II. German was considered the lingua franca of the Empire, and Empire's elite consisted primarily of German-speakers. The struggle between the many ethnic groups of the Empire and German-speakers defined the social and political landscape of the Empire from the 1870s, after the Compromise of 1867, which granted renewed sovereignty to the Kingdom of Hungary, until the dissolution of the Empire after the First World War.

After the Austrian defeat in the Battle of Königgrätz of 1866, and the unification of what was then known as "Lesser Germany" under Prussian stewardship in 1871, the German Austrians in the Austro-Hungarian Empire felt that they had wrongly been excluded from the German nation-state, whilst other ethnicities within the Empire were tearing at its fabric. Conflict between Germans and Czechs grew particularly tense in 1879, when minister-president Viscount Taaffe did not include the German-Liberal Party (German: Deutschliberale Partei) in the government of Cisleithania. This party was considered the main representative of the German-speaking middle class, and as such, the German National Movement went on to accuse the Party of not fighting for the rights of German-speakers within the Empire. The "German School League" (German: Deutscher Schulverein) was formed in 1880 to protect German-language schools in parts of the Empire where German speakers were a minority. It promoted the establishment of German-language schools in communities where public funding was used for non-German schools.

A consortium of German nationalist groups and intellectuals published the Linz Program in 1882, which demanded the recognition of German predominance in the Empire, along with the complete Germanisation of the Empire. This manifesto was signed by the radical German nationalist Georg von Schönerer, Vienna's populist, pro-Catholic, and royalist mayor Karl Lueger, and the Jewish social democrat Victor Adler. The diverse signatories of the Linz manifesto split ideologically after Schönerer revised it to add an "Aryan paragraph" in 1885.

Schönerer founded the "German-National Association" (Deutschnationaler Verein), and later, in 1891, the "Pan-German Society". He demanded the annexation of all German-speaking territories of Austria-Hungary to the Prussian-led German Empire and rejected any form of Austrian pan-ethnic identity. His radical racist German nationalism was especially popular amongst the well-educated intelligentsia: professors, grammar school teachers, and students. School administrations tried to counteract these sentiments by encouraging civic pride, along with a "cult of personality" around the Emperor, but these efforts were largely unsuccessful. Vienna mayor Karl Lueger even tried to dismiss all "Schönerians" from city school administrations, but this too failed. National-minded students rather identified with the Prussian-led German Empire than with the multiethnic Dual Monarchy. Many idolised the German chancellor Otto von Bismarck, victor in the Battle of Königgrätz.

Members of the pan-German movement wore blue cornflowers, known to be the favourite flower of German Emperor William I, in their buttonholes, along with cockades in the German national colours (black, red, and yellow). Both symbols were temporarily banned in Austrian schools. Like Schönerer, many Austrians hoped for an Anschluss with Germany. However, although many Austrians accepted the ideas of the various pan-German movements and felt part of the German nation, they accepted the existence of the Austro-Hungarian Empire, were loyal to the Habsburg dynasty, and wanted to preserve the sovereignty of Austria.

German nationalists protested vehemently against minister-president Kasimir Count Badeni's language decree of 1897, which made German and Czech co-official languages in Bohemia and required new government officials to be fluent in both languages. This meant in practice that the civil service would almost exclusively hire Czechs, because most educated Czechs knew German, but not the other way around. The support of ultramontane Catholic politicians and clergy for this reform triggered the launch of the "Away from Rome" (German: Los-von-Rom) movement, which was initiated by supporters of Schönerer and called on "German" Christians to leave the Roman Catholic Church.