Süddeutsche Monatshefte ("South German Monthly", also credited as Süddeutscher Monatshefte) was a German magazine published in Munich between January 1904 and September 1936. After beginnings as an art and literary venue, liberal but highly critical of modernism, it made a turn toward politics before World War I. Especially supportive of German conservatism, it was also sympathetic toward Völkisch ideologists, and published propaganda in favor of militarist politicians such as Alfred von Tirpitz. Having for its founder and editor Paul Nikolaus Cossmann, an assimilated Jew, Süddeutsche Monatshefte was generally antisemitic—strongly so after 1920, when it hosted calls for racial segregation.

Its publication of conspiracy theories such as the stab-in-the-back myth paved the way for Nazi propaganda, but Süddeutsche Monatshefte was more closely aligned with the mainstream right. It played a part in conspiratorial alliances supporting the policies of Gustav von Kahr, although it also had Conservative Revolutionaries among its core contributors. In its late years, Süddeutsche Monatshefte turned to Bavarian nationalism and Wittelsbach loyalism, becoming a target for the Nazi regime. Cossmann was imprisoned for dissidence, then deported for his Jewishness; Leo Hausleiter [de] took over, leading Süddeutsche Monatshefte until its disestablishment in 1936.

Established as a mainly social-liberal tribune by Cossmann, a Jewish writer who had converted to Catholicism, Süddeutsche Monatshefte initially sought to reaffirm the cultural importance of Southern Germany and solidify its symbiotic relationship with Prussia, creating cultural bridges between Catholics and Protestants. Joining the directorial staff in the first edition was liberal pastor-politician Friedrich Naumann (its political director to 1913), who shared editorial oversight with painter Hans Thoma and composer Hans Pfitzner. Protestant social reformer Martin Rade [de] and Joseph Schnitzer, a Modernist Catholic, were noted guest writers, with Cossmann acting as neutral host. During the federal election of 1907, the magazine hosted debates between Schnitzer and Center Party militant Martin Spahn [de], on Political Catholicism and its role in society (a divisive one, according to Schnitzer). However, according to historian Adam R. Seipp, Süddeutsche Monatshefte was mainly an interface for traditional Munich—Catholic, "deeply conservative", "suspicious of outside influences", and antithetical to the modernist Simplicissimus.

Cossmann managed to attract important writers to the magazine's permanent staff, including Josef Hofmiller [de] and Karl Alexander von Müller. In its early issues, Süddeutsche Monatshefte hosted mainly essays by the likes of Hofmiller (such as his 1909 putdown of the modernist author Robert Walser), Carl Spitteler, and Karl Voll, and poetry by Paul Ilg [de].

Some of the cultural and social chronicles had nationalist undertones, debating over the requirements of German modernization. As Anglophiles, Hofmiller, Lujo Brentano, and Theodor Vogelstein [de] suggested fusing Anglo–American lessons in modernity with the German Volkstum, to make Germany a more competitive capitalist nation; in 1906, a Dr. Paul Tesdorf went further, promoting eugenics as a means to engineer a better people. In contrast, Naumann and other authors worried about finance capitalism and oligopolies, exhorting a German nationalism based on "democratic capitalism" or syndicalism, and following closely the development of Marxist revisionism. In a February 1906 obituary for the "legal socialist" Anton Menger, Eugen Ehrlich commented that the term "socialism" had virtually lost its mystique.

The magazine took a distinctly liberal position on education reform, with Rade supporting the Jewish studies movement. Most of the contributors, in particular Gustav Wyneken, were critics of the Herbartian educational tradition; Wyneken's polemics with the more conservative Friedrich Wilhelm Foerster were taken up by Süddeutsche Monatshefte. In 1909, the journal was also one of the first to host Hans Driesch's philosophical tracts, discussing the concept of becoming in history and nature. In 1913, it aired Moritz Geiger's grievances against experimental psychology, implicitly a defense of classical phenomenology.

Debates about innovation were carried into the artistic realm. An early contributor, Henry Thode, wrote articles which censured modern art from conservative and antisemitic positions, attacking modernist critics such as Julius Meier-Graefe. In 1911, the debate was taken further: Süddeutsche Monatshefte hosted both Carl Vinnen's manifesto against French "invasion" in German art, as well as the more cautious, pro-modernist, replies to Vinnen, from: Thoma, Lovis Corinth, Gustav Klimt, Max Klinger, Max Slevogt, Count Kalckreuth, Wilhelm Trübner, and Auguste Rodin. In various other issues, Süddeutsche Monatshefte carried polemical essays by aestheticists such as Rudolf Borchardt and Paul Zarifopol.

In January 1913, Süddeutsche Monatshefte made official its doctrinal links with anti-democratic conservatism: Robert von Pöhlmann published an article condemning majoritarianism, demanding instead the remodeling of Germany into a Kulturstaat ("civilization-state"), with a politically enshrined social stratification. Naumann resigned in protest against veiled accusations him in Pöhlmann's article, but also because the magazine had discarded liberal democracy.