Rabbi Avraham Yeshaya Karelitz, known as the Chazon Ish after his series of books ("Ish" alludes to the initials of his name), was born on 11 Cheshvan 5639 (7 November 1878) in Kosava, in the Grodno province of the Russian Empire (today Belarus). His father, Rabbi Shmaryahu Yosef Karelitz, was the town's rabbi; his mother, Rasha Leah, was the daughter of the previous rabbi, Rabbi Shaul Katzenellenbogen.

Apart from a brief period in the study circle of Rabbi Chaim Ozer Grodzinski in Vilna, he never attended cheder or yeshiva and apparently never received formal semichah. Taught by his father and a private tutor, Rabbi Moshe Tuvia, he was largely self-taught. He married Batya Bei of Kvedarna in Lithuania, who ran a shop so that he could learn; the couple had no children but helped raise his Greineman and Kanievsky nephews.

In 5671 (1911) the first volume of Chazon Ish appeared in Vilna, published anonymously by his brother and without approbations. Settling in Vilna in 1920, he grew close to Rabbi Chaim Ozer Grodzinski. On 16 Tammuz 5693 (10 July 1933) he immigrated to the Land of Israel and settled in Bnei Brak, which, largely thanks to him, became one of the strongholds of Haredi Judaism. There, in 1936, he founded one of the country's first kollels.

Though he never held an official rabbinic post, he was one of the leading halachic authorities of his time. He helped found yeshivot after the Holocaust and supported farmers who kept Shemittah without relying on the sale of land (heter mechirah). In 1952 he received Prime Minister David Ben-Gurion, answering him with the parable of the two camels: the unladen camel must make way for the one carrying a load.

Works: the Chazon Ish series on Talmud and halachah, Emunah uBitachon, and his letters (Iggerot Chazon Ish).

He passed away on Friday night, 15 Cheshvan 5714 (24 October 1953), in Bnei Brak. Tens of thousands followed his funeral, and he was buried in the Shomrei Shabbat cemetery in Bnei Brak.