1310 - C. 1375 NISSIM BEN REUBEN GERONDI (Rabbenu Nissim - the Ran) (Spain)
Talmudist, scholar and physician. He was recognized as one of the most authoritative halachic interpreters of his generation. His halachic commentary on Alfasi is considered a standard text. His commentary on Tractate Nedarim is printed together with the Talmud and is used instead of Rashi which is not extant for that section of the Talmud. The exact date of his death is unknown. It is presumed he died while being held captive in prison.