Estimé was born to a poor family in the small city of Verrettes, in the Artibonite Valley. His father, Alciné Estimé and mother Florencia Massillon died while he was young. A well-to-do uncle, Estilus Estimé, brought him to Port-au-Prince, Haiti's capital, and financed his education at law school. He graduated and briefly practiced law before becoming a teacher. After the government of Louis Borno expelled him for sedition, Estimé joined Haiti's nationalist movement in 1930 and became an outspoken opponent of the United States occupation of Haiti.