The second of Hyam and Ceclia Woolf Moise’s two children, Edwin Warren Moïse was born in Charleston, where his grandparents Abraham and Sarah had settled, fleeing Saint-Domingue after the Haitian Revolution, when his Edwin’s father was still a small child. He and his brother, Theodore, were brought up within a large extended family of cousins and aunts and uncles, attending Congregation Beth Elohim. While much of the family would remain in Charleston, leaving marks on the city—his aunt, Penina, a prolific poet—but Edwin’s future, like that of his brother, an itinerant painter, lay elsewhere.

After training at the Medical College of Charleston, he married Priscilla Lopez, daughter of David and Priscilla Lopez, in 1835. They settled in Woodville, Mississippi, an affluent cotton town, where Moise worked as a physician. There first child, Cecilia, was born there in 1836, and in 1839 Priscilla died, four days after giving birth to twins, Sallie and Theodore.

Soon after this tragedy, the family moved to New Orleans, where Moïse took up work as a lawyer. He was elected to the Louisiana House of Representatives, eventually serving as speaker. Meanwhile, he married Louise Hubert, with whom he would have five more children. Moïse served as a United States Attorney and in 1856 was appointed attorney general of Louisiana by Governor Robert C. Wickliffe. A staunch secessionist, he served, during the Civil War, as a Confederate district court judge.