Moshe Feinstein
He was a community Rabbi in Communist Russia for over twenty years under increasing pressure, and finally moved to New York City in the late 1930s where he lived for the rest of his life. He died in 1986 on the Hebrew calendar date of 13th of Adar II, 5746.
He authored an eight-volume set of Halachic responsa called Igroth Moshe (Letters of Moshe), which is still in wide usage in Orthodox Judaism circles. Talmudic novellae appeared as Dibroth Moshe (Moshe's words), and novellae on the Torah appeared posthumously as Darash Moshe (Moshe expounded).
He was the rabbinic head of Agudath Israel of America.
He lived into his nineties, and was the rosh yeshiva (dean) of the yeshiva Mesivta Tiferes Jerusalem. He established a branch of his yeshiva on Staten Island, New York, headed by his son Rabbi Reuven Feinstein. His son Rabbi David Feinstein heads the Manhattan branch.