Naumann advocated an imperialist foreign policy, laying out Germany's claim to dominate Central Europe in his 1915 Mitteleuropa plan.

From 1883 he worked at the Rauhes Haus charity institution established by Johann Hinrich Wichern in Hamburg, before in 1886 he took over the rectorate of Lengenberg near Glauchau in Saxony.

Starting from 1894 he published the weekly magazine Die Hilfe ("The Help") to address the social question from a non-marxist middle class point of view.

To this end he wrote the short book, Soziale Briefe An Reiche Leute ("Social Letters to Wealthy People") published in Göttingen in 1895.

[2] During the 1890s Hamidian massacres, Naumann became known for expressing anti-Armenianism in Die Hilfe including the famous "potter's quote" in which Naumann quoted a German potter, whom he met during his journey to the Near East in Constantinople, as stating: I am a Christian and hold "Love thy neighbor" as the first commandment, and I say that the Turks did the right thing when they beat the Armenians to death.

Later in his life, Naumann worked for an approachment of German social democratic and liberal movements, but faced major opposition from conservatives.

On the eve of World War I, Naumann proved to be a monarchist, but his sympathy for the German emperor Wilhelm II had vanished since the well-known Daily Telegraph Affair of 1908.

[5] In 1919, Friedrich Naumann was among the founders of the social liberal German Democratic Party (Deutsche Demokratische Partei, DDP) with Theodor Wolff and Hugo Preuss.

He shared his views with the intellectual circles he frequented, including not only Max Weber, but also Lujo Brentano, Hellmut von Gerlach, young Theodor Heuss, his wife Elly Heuss-Knapp, and Gustav Stresemann.

[citation needed] According to the historian Götz Aly, Naumann "distorted liberalism beyond recognition and completed the turn to nationalist power and popular welfare politics".

While Naumann was not a forerunner of the Nazis' antisemitism, Aly accuses him of having "combined social, imperial, and national thought into a cohesive intellectual current that could eventually blend with the NSDAP's mindset".