Reb Itzelle Peterburger

Rabbi Yitzchak Blazer (1837–1907), also known as Reb Itzelle Peterburger, was one of the early important leaders of the Musar movement. He was a student of the founder of the movement, Rabbi Yisrael Salanter, and was responsible for publishing many of Salanter's letters in Or Yisrael. Rabbi Blazer became the chief rabbi of St. Petersburg in 1861-2, when he was only 25 years old. From 1880 to approximately 1891, he served as the head of the Kovno Kollel in Kaunas, Lithuania, which was founded by Salanter.