Fremiet was born in Paris into an artistic family. His Aunt Sophie, wife of the celebrated sculptor Rude, gave him his first lessons in drawing; later he worked with an uncle, the natural history painter, Werner. Fremiet covered a variety of unpretentious, even macabre, occupations in his pursuit of a career in art before being accepted as a pupil by his uncle, Rude. He executed lithographic drawings, modelled sacred subjects for commercial sale, made anatomical specimens in wax for the Museum of Medicine, and was at one time painter to the Morgue, repairing blemishes on bodies that were to be preserved. Attempting to discourage Fremiet, his uncle Rude had pointed out the hazards and difficulties of a sculptor's career, but without success, and his highest hopes were realised when he was taken into the famous studio at the Rue d'Enfer. Fremiet's determination proved worthwhile. He became one of the most successful and important sculptors in nineteenth century France. He received numerous prizes and awards during the course of his long and successful career. He succeeded Antoine-Louis Barye as Professor of Drawing at the Museum of Natural History; was made a Grand Officer of the Legion of Honour, and was also elected as an Associate of the Royal Academy in London. He was over-loaded with state commissions; it is said that he received many through the influence of Rude, that should have gone elsewhere, but, be that as it may, he satisfied his many patrons and was a popular and respected figure.

The many monumental works commissioned for Paris and the provinces of France inspired appreciation of Fremiet's work which spread rapidly abroad, and his sculptures were placed in such diverse places as Bucharest, Baltimore and Port Said. His 'Jeanne d'Arc', the gilded bronze equestrian statue which stands in the Place de Rivoli in Paris, is a sculpture which captures pride and spirit in both horse and rider. Particularly emphatic that he was not an animal sculptor, it is ironic indeed that it is his small sculptures of animals that has brought his name to the fore today.

Fremiet was a tireless worker and an ardent researcher, not only in the anatomical field, but also in the numerous varieties of dress he needed for his monumental portraits and equestrian groups. The uniforms, armour, saddlery and harness that Fremiet depicted were all meticulously correct.