Arles (ancient Arelate) in the south of Roman Gaul (modern France) hosted several councils or synods referred to as Concilium Arelatense in the history of the early Christian church.
The first council of Arles in 314 formally condemned the heresy of Donatism. It began as an appeal by the Donatists to Constantine the Great against the decision of the Council of Rome in 313 at the Lateran under Pope Miltiades. The appeal turned out unfavorably to the Donatists who afterwards became enemies of the Roman authorities. The Council of Arles was the first called by Constantine and is the forerunner of the First Council of Nicaea. Augustine of Hippo called it an Ecumenical Council.
It excommunicated Donatus and passed twenty-two canons concerning Easter (which should be held on the same day throughout the world, rather than being set by each local church), against the non-residence of clergy, against participation in races and gladiatorial fights (to be punished by excommunication), against the rebaptism of heretics, and on other matters of discipline. Clergymen who could be proven to have delivered sacred books in persecution (the traditores) should be deposed, but their official acts were to be held valid. The assistance of at least three bishops was required at ordination.
Called in support of Arianism. It was attended, among others, by two papal legates. The legates were tempted into rejecting communion with Athanasius and refused to condemn Arius, an act which filled Pope Liberius with grief.