(d. 1770s), Polish communal leader and lobbyist. Barukh ben David Yavan was born at the beginning of the eighteenth century in Konstantynów, Volhynia. He came from an eminent family that descended from Rabbi Shalom Shakhnah of Kraków and received an education encompassing not only traditional Jewish learning (he studied Talmud under Ya‘akov Yehoshu’a Falk) but also an extensive non-Jewish curriculum, including German, French, Latin, and Polish.
Yavan was arguably the best-connected Jew in the Polish–Lithuanian Commonwealth. He was a prominent agent at the court of the secretary of the Royal Polish Treasury—Karol Sedlnicki—and a shtadlan (intercessor) on behalf of the Council of Four Lands. In the early 1740s, he met Count Heinrich Brühl, the all-powerful minister of Augustus III, who was both elector of Saxony and king of Poland. During the War of the Austrian Succession, Yavan carried out a number of secret missions on behalf of Brühl and the king, and in October 1744 was involved in back-and-forth negotiations between Frederick II of Prussia and Augustus III. Yavan brought to Dresden the Prussian offer to accept the inheritance of the Polish crown by the Wettin dynasty in exchange for Saxony rescinding its alliance with Maria Theresa.
During the Emden–Eybeschütz controversy (a dispute that resulted when Rabbi Ya‘akov Emden accused his colleague Yonatan Eybeschütz of Sabbatianism), Yavan sided with Emden; at the session of the Council of Four Lands in Konstantynów in 1751 Yavan attacked a prominent supporter of Eybeschütz, Avraham Ḥayims (ben Ḥayim) of Lublin, and his son Ḥayim. Avraham had much support in the council but Yavan convinced his patron Sedlnicki to intervene in the debate and order Avraham ben Ḥayim’s arrest. Yavan’s ties to Emden were cemented when his son married Emden’s daughter, Neḥamah.
Following the eruption of the Frankist affair in 1756, Yavan wrote to Emden describing the events and asking for advice. Emden advised that the Council of Four Lands try to convince the priests that both Jews and Christians should condemn the Frankists equally and that the Frankists should be burned at the stake by Christian authorities. Yavan decided to act upon Emden’s advice and worked at turning the Frankists over to gentile authorities. During the Kamieniec disputation (1757), he interceded with Brühl, who put him in touch with the papal nuncio in Warsaw, Bishop Nicolaus Serra. After Bishop Mikołaj Dembowski’s verdict at Kamieniec condemning the Talmud, Yavan intervened with the nuncio and managed to save numerous copies of the Talmud from burning. During the Lwów disputation (1759), Yavan was in daily contact with Brühl and Serra. Through the nuncio, he sought direct papal intervention in the Frankist affair and forwarded documents pertaining to Frankism to Rome.
While imprisoned by Roman Catholic authorities, Frank made contact with the Russians, promising that in exchange for his freedom he would lead 20,000 Jews to convert to Greek Orthodoxy. Yavan acted swiftly, traveling to Saint Petersburg to convince the Russians that the Frankists’ intentions were not sincere. Yavan told the Russians that the Frankists had already changed their religion four times: from Judaism to the “faith of Shabetai Tsevi,” then to Islam, back to Sabbatianism, and finally to Roman Catholicism. Greek Orthodoxy would thus be the fifth religion they professed. Acting upon Yavan’s information, the Russians rejected Frank’s offer. After Brühl’s death in 1763 Yavan moved to Dresden; he is presumed to have died some time in the 1770s.
Jacob Emden, Torat ha-kena’ot (Lemberg, 1869/70); Israel Halpern and Yisra’el Bartal, eds., Pinkas Va‘ad Arba‘ Aratsot: Likute takanot, ketavim u-reshumot (Jerusalem, 1989/90); Pawel Maciejko, “Baruch Yavan and the Frankist Movement: Intercession in the Age of Upheaval,” Jahrbuch des Simon-Dubnow-Instituts 4 (2005): 333–354; Scott Ury, “The Shtadlan of the Polish-Lithuanian Commonwealth: Noble Advocate or Unbridled Opportunist,” Polin 15 (2002): 267–299.