To my knowledge I am not a direct Horowitz descendant, only an in-law, so my interest in the following is purely a historical-academic impulse.
There was a rabbi by the name of Moshe 'Meshel' HaLevi Horowitz who founded the well-known Eishishok (Eisiskes) Yeshiva (aka as the Eishisok Kibbuts Prushim), sometime in the early 19th Century. The newly published Eishishok Yizkor Book states: "We may assume that this Rabbi Moshe was Rabbi Moshe Berabibi(son of ) Aharon Halevi Horwitz, an Eishishok teacher in the time of Hagra, and one of the three Rabbis in Lithuania called upon to decide in the controversy of the Vilna Congregation, between Rabbi Shmuel Berabbi (son of) Avigdor the last President of the Court in the Vilna congregation and his congregation.", p. 12.
Since the Vilna Congregation controversy peaked circa 1785 and the GRA died in 1797, I surmise, subject to further confirmation, the YB statement is referring to Rav Aharon as being the one who was the teacher in the time of the GRA and who called to decide the controversy, rather than his son Moshe. Moshe was the founder of the Yeshiva, however (which I have from another reliable source).
The inquiry then is for any details regarding the identity and genealogy of Rabbi Aharon HaLevi Horowitz of Eishishok, one of the three Rabbis called upon to decide the Vilna Congregation controversy. Is this Rabbi Aharon currently found on the GENI tree?
Most gratefully,
Adam Cherson
