A great Jewish sage, 1135-1204, Rabbi Moses ben Maimon (called "Maimonides" in English: son of Maimon. In Hebrew he's generally called "Rambam," from the initials Rabbi Moses ben Maimon). He was born in Spain, but moved to around a lot, to Morocco and Israel, and settled in Egypt, where he became the personal physician to the Sultan. He wrote many books of law and philosophy--some of which got him in a lot of trouble with the contemporay Jewish rabbinate. Some branded him a heretic, even bringing the French Inquisitors in on the argument.
His works are widely studied today, and with reason: he was an extraordinarily deep thinker. His philosophy is influenced by Aristotle, and tended to analyze religion in logical ways.
His most famous contributions to Jewish literature include his Mishneh Torah, a book of law, and his Guide to the Perplexed, a philosophical work.