(1858–1913), socialist, publisher, writer, and editor of the first Polish-language Jewish daily newspaper. Born to a well-to-do assimilated banking family in Warsaw, Stanisław Mendelsohn attended medical school. As a student at Warsaw University in 1875–1877, he helped to establish the first Polish socialist circle.
In 1878, Mendelsohn helped to write the Program of Polish Socialists, the founding document of the socialist movement in his country. Forced into exile, he moved to Geneva, where he founded and financed the first two Polish socialist journals, Równość (Equality; 1879–1881) and Przedświt (Dawn; 1881–1893). Mendelsohn continued to play a significant role in shaping the orientation of the movement throughout the 1880s and early 1890s, promoting the change from an internationalist to a pro-independence stance. In Przedświt, Mendelson forcefully argued that democracy could come to the Polish lands only after separation from Russia.
Mendelson was among the organizers of the founding convention of the Polish Socialist Party (PPS) in November 1892 in Paris. He composed the Outline Program of that party, which the convention approved, and which remained the official party platform until 1905. In 1893, he returned to Russian Poland and formed the first local party divisions.
Mendelson also shaped the movement’s general position on the Jewish question. As a Polish delegate to the Brussels Congress of the Second International (1891), he cowrote a resolution on this subject. Calling for assimilation and opposition to Jewish separatism, the resolution stated as follows: “We resolve that Yiddish-speaking workers have no other means of liberation than to fuse with the proletarian ranks of a given country.” In “On the Intensification of Antisemitism in Poland” (1892), Mendelson condemned antisemitism in Polish lands as a cover for antidemocratic impulses within Polish society. Simultaneously, he warned Jews about the dangers of separatism. The only solution, Mendelson argued, was to create a Polish democratic republic under socialist rule.
An enigmatic figure, Mendelson abruptly left the party in late 1893 over ideological disputes. In the years leading to World War I, he lived in Lemberg (Lwów) with his wife, Maria Jankowska-Mendelson, and served as a correspondent for several Polish newspapers. He also wrote a history of the 1871 Paris Commune (Historia ruchu komunalistycznego we Franci 1871; 1904). In response to outbreaks of Polish political antisemitism in 1905–1912, he increased his involvement in Jewish affairs, rejected assimilationism, and became interested in Zionism.
Three years after his wife died in 1909, Mendelson married Maria Sokolow, making him the son-in-law of the celebrated Warsaw Zionist Naḥum Sokolow. Mendelson also was the founding editor of the first Polish-language Jewish daily newspaper, Przegląd Codzienny (Warsaw; 1913–1914), a political, social, and literary Jewish daily that defended Jewish interests.
Władysław Bieńkowski, “Mendelson (Salomon Naftali) Stanisław,” in Polski słownik biograficzny, vol. 20 (Warsaw, Wrocław, and Kraków, 1975), pp. 421–427 (1975); Alexander Guttermann, “Manhige tenu‘at ha-po‘alim ha-polanit mi-mots’a yehudi: Shorashehem zehutam ve-yaḥasam li-kelal Yisra’el,” Me’asef 14–15 (1984–1985): 35–60; Moshe Mishkinsky, “Polish Socialism and the Jewish Question on the Eve of the Establishment of the Polish Socialist Party and the Social Democracy of the Kingdom of Poland,” Polin 5 (1990): 250–272.