Izhbitza-Radzin is the name of a dynasty of Hasidic rebbes. The first rebbe of this dynasty was Rabbi Mordechai Yosef Leiner, author of Mei Hashiloach, in the city of Izhbitza. (Izhbitza is the Yiddish name of Izbica, located in present-day Poland.) Mordechai Yosef founded his own Hasidic movement in the year 5600 (1839), leaving the court of Rabbi Menachem Mendel of Kotzk.