Neologs (Hungarian: neológ irányzat, "Neolog Fraction") are one of the two large communal organizations among Hungarian Jewry. Socially, the liberal and modernist Neologs were more inclined toward integration in general Hungarian society since the Era of Emancipation in the 19th century. This was their main feature, and they were largely the representative body of urban, assimilated middle- and upper-class Jews. Religiously, the Neolog rabbinate was influenced primarily by Zecharias Frankel's Positive-Historical School, from which Conservative Judaism evolved as well, though the formal rabbinical leadership had little sway over the largely assimilationist communal establishment and congregants. Their rift with the traditionalist and conservative Orthodox Jews was institutionalized following the 1868–1869 Hungarian Jewish Congress, and they became a de facto separate denomination. The Neologs remained organizationally independent in the territories ceded under the terms of the 1920 Treaty of Trianon, and are still the largest grouping among Hungary's Jews today.
In the early 19th century, when first attempts to reform Judaism under the influence of Enlightenment were made, they had little impact in the Kingdom of Hungary. Rabbi Aaron Chorin of Arad was an early proponent of religious modification; from the publication of his 1803 book "Emeq ha-Shave" and onwards, he dismissed Practical Kabbalah and the Book of Radiance, authored guidelines for modernizing Judaism according to Talmudic principles and sought to remove what he regarded as superstitious or primitive elements, like spitting in the prayer of Aleinu. In 1818, Chorin was one of the few rabbis who backed the Hamburg Temple. However, while drawing the ire of Hungarian Orthodoxy headed by Rabbi Moses Sofer of Pressburg, he had but meager following in his country. The rural character and social seclusion of the Jews in the kingdom offered little incentive for his endeavor.