Rav Yitzchok Meir, son of Rav Avrohom Yehoshua Heschel, was born in Mezibuzh on 21 Kislev in the year 1861, 5622/תרכ''ב. He was a scion of the Apta Mezibuzh dynasty. His father-in-law, Rav Mordechai Shraga Friedman of Husyatin, was descended from the Mezritch Ruzhiner dynasty. On February, 10, 1881, he married his father's first cousin, Gitel, daughter of the Husyatiner, Rebbe Mordechai Feivush Friedman. He lived in Husyatin until the death of his father-in-law on June 27, 1894. From the age of 14, Rav Yitzchok Meir sat in his father-in-law’s home and was deeply influenced by him, to the point that he accepted upon himself all of his father-in-law’s customs.
In the year 5654/תרנ''ד, he began to hold court as the Kopishnitzer Rebbe, not far from Husyatin, and the area soon grew to be a large stronghold of Chassidus. Rav Yitzchok Meir was renowned for his wonder-working and miracles. He was also outstanding in giving tzedaka, and sent large sums to strengthen the yishuv in Eretz Yisroel. In 5672/תרע''ב, he participated in a gathering of Rebbes in Czernowitz, where the Histadrut HaCharedim was founded – the forerunner of Agudas Yisroel.
During the First World War, Rav Yitzchok Meir fled Kopishnitz and went to Vizhnitz at the behest of his dear friend and colleague Rav Yisroel of Vizhnitz. From there, he went to Vienna, where he ultimately settled. Once the war ended, he travelled to his Chassidim in Galicia and Bukowina.
After the davening on the first day of Rosh Hashana in the year 5696/תרצ''ו , Rav Yitzchok Meir returned his pure, holy soul to his Maker. He was laid to rest in Vienna, and an ohel was erected on his kever.
His sons were Rav Avrohom Yehoshua Heschel, who succeeded him in Vienna; Rav Moshe, who perished in the Holocaust; Rav Sholom Yosef, who lived in Eretz Yisroel; and Rav Mordechai Shraga of Tel Aviv. His daughters were Bluma, the wife of Rav Avrohom Yaakov of Sadigura, Tel Aviv; Chava, the wife of Rav Eliezer of Vizhnitz (author of Damesek Eliezer); and Miriam, the wife of Rav Avrohom Yehoshua Heschel of Tarnipol.
