Nathan Birnbaum
Authors: Olson Jess J. 
Published: January 2021

Nathan Birnbaum (b. 1864–d. 1937), also known by the pseudonym Mathias Acher (“another Mathias”), was a journalist, theorist of Jewish nationalism, and political activist. Birnbaum was a pioneer in the emergence of both secular Jewish nationalism and Orthodox political organization. Deeply affected by his exposure to rising anti-Semitism in fin-de-siècle Vienna and alienated by what he would term “assimilation mania” (Assimilationssucht), Birnbaum’s ideology was shaped early by two themes that developed throughout his career: belief that there was an intrinsic, unique Jewish identity, and that this identity could be activated as a solution to the oppression afflicting European Jews. Birnbaum’s early work integrated models of central European nationalism filtered through the writings of Moses Hess, Peretz Smolenskin, and Leon Pinsker. In the wake of anti-Jewish violence in Russia in 1882, Birnbaum and other Jewish students at Vienna University founded Kadimah, the earliest Jewish nationalist organization in central Europe. He cultivated an important presence among central European Jewish nationalists, and he was a significant influence on a young generation of “cultural” Zionists. In the early 1890s, he coined the term “Zionism” (Zionismus) to describe Palestine-oriented Jewish nationalism. When Theodor Herzl arrived in Zionist circles in 1896, he sidelined Birnbaum along with nearly everyone else who had preceded him in the movement, but Birnbaum’s opinion on the nature of authentic Jewish identity was already evolving. He eventually became an internal, and ultimately outside, critic of Zionism, concluding that an organic Jewish identity already existed in the folkways, Yiddish language, and communities of eastern European Jews. As an extension of this, he led in organizing the first conference of the Yiddish language in 1908. In the aftermath of the conference, Birnbaum deepened his engagement with the Yiddish language and eastern European Jewish culture and increasingly turned his thoughts to issues of spirituality and religion. After the outbreak of the First World War, Birnbaum announced himself a “ba’al teshuva,” a penitent returnee to Torah-observant Judaism. He was embraced by the Agudah, and his skills as a journalist and activist were put to use in Agudah organizing. Now Birnbaum revolutionized his understanding of the foundation of Jewish identity. Maintaining the ideal of Jewish authenticity as the only route to Jewish cohesion, Birnbaum rejected his earlier ethno-nationalist understanding of Jewish identity, replacing it with Orthodox religious observance and belief in the Torah. He aligned himself with a Hasidic religiosity that was an organic extension of his admiration for eastern European Jewry. A transformation that earned him respect in the Orthodox world and derision among the secular nationalists he had left behind, Birnbaum considered his change consistent with his views on Jewish authenticity. As the situation of European Jewry declined in the late 1920s and 1930s, Birnbaum felt vindicated in his dim view of the possibility of Jewish life outside of a religious identity, and wrote in this vein for the rest of his life. He died in Scheveningen, The Netherlands, in 1937.