The family chiefly descends from Rabbi Joseph HaLevi, who settled in Hořovice, Bohemia, (German: Horschowitz or Horowitz) in 1391 and adopted the surname "Ish-Horowitz" (lit.

[1] Zerachiah HaLevi traced his lineage to the Yizhari family of Girona; he asserted paternal descent from Heman the Ezrahite, the grandson of the Biblical prophet Samuel.

Heman, in turn, was a direct paternal descendant of Yizhar, the son of Kehath, who was the eponymous ancestor of the Yizhari family of Girona.

His son, Shabbethai Horowitz (1590–1660), was a prominent Talmudist and rabbinic figure in Ostroh, Fürth, Frankfurt am Main, and Vienna.

[6] R. Pinchas's son R. Tzvi Hirsch Horowitz (1753-1817) succeeded him as Chief Rabbi of Frankfurt and authored the work "Macheneh Levi".

R. Meir's great-grandson was R. Yisrael Friedman of Ruzhin who is the progenitor of the Bohush, Boyan, Chortkov, Husiatyn, Sadigura, and Shtefanesh Hasidic dynasties.

R. Yosef Yozel Horwitz (1847–1919), was an important rabbi in the Musar movement, founding seventy yeshivos across Eastern Europe.

In 2016 historian and genealogist Edward Gelles established through autosomal DNA the traditional belief concerning the descent of the Levitic Horowitz lines from the Yizhari family of Girona.

[12] In 2017 the journal Scientific Reports confirmed that the genealogical records for three of the individuals with the Horowitz surname converged to a common male ancestor born at 1615 CE or 402 ybp.