Judah Leib "Leopold" Löw was a Hungarian rabbi, regarded as the most important figure of Neolog Judaism.

Neologs are one of the two large communal organizations among Hungarian Jewry. Socially, the liberal and modernist Neologs had been more inclined toward integration into 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, although 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 those territories ceded under the terms of the 1920 Treaty of Trianon, and are still the largest group among Hungary's Jews.