The Jewish community in France is estimated to be 480,000-500,000 but depends on the adopted definition. there were Jews at Vienne and Gallia Celtica; in the year 39 at Lugdunum (i.e. An early account praised Hilary of Poitiers (died 366) for having fled from the Jewish society.
French Jewish communities are concentrated in the metropolitan areas of Paris, which has the largest population; Marseille, with the second-largest population of 70,000; Lyon, Nice, Strasbourg, and Toulouse. The emperors Theodosius II and Valentinian III, addressed a decreee to Amatius, prefect of Gaul (9 July 425), that prohibited Jews and pagans from practising law or holding public offices (militandi), so that Christians should not be subject to them and possibly incited to change their faith.
Their association with fellow citizens was generally amicable, even after the establishment of Christianity in Gaul.
Louis le Débonnaire (814–833, 834-844), faithful to the principles of his father, granted strict protection to Jews, whom he respected as merchants.
Like his father, Louis believed that 'the Jewish question' could be solved with the gradual conversion of Jews; according to medieval scholar JM Wollace-Harill, some people believed this tolerance threatened the Christian unity of the Empire, which led to the strengthening of the Bishops at the expense of the Emperor.
Charlemagne fixed a formula for the Jewish oath to the state.
He allowed Jews to enter into lawsuits with Christians.