The Council of Philippopolis in 343, 344, or 347 was a result of Eastern bishops leaving the Council of Sardica to form their own counter council. In Philippopolis, they excommunicatedPope Julius as well as their rivals attending the synod in Sardica. As a result, the Arian controversy was perpetuated, rather that resolved, as was the original intention of the Co-AugusiConstans and Constantius along with Pope Julius in calling the Council of Sardica.
The Council of Sardica was one of the series of councils called to adjust the doctrinal and other difficulties caused by the christological Arian heresy (from the Catholic and, later, Orthodox points of view), held most probably in 343.
Athanasius and other bishops alternately condemned and vindicated by councils in the East and the West; desirous, also, of settling definitively the confusion arising from the many doctrinal formulx in circulation, suggested that all such matters should be referred to a general council.
Though the form of the proposed creed was presented to the council, it was bit inserted in the encyclical addressed by the council to "all the bishops of the Catholic Church".
On his second banishment from Alexandria, Athanasius came to Rome, and was recognized as a regular bishop by the synod held in 340.
It was through the influence of Julius that, at a later date, the council of Sardica in Illyria was held, which was attended only by seventy-six Eastern bishops, who speedily withdrew to Philippopolis and deposed Julius, along with Athanasius and others.
The Western bishops who remained confirmed the previous decisions of the Roman synod; and by its 3rd, 4th and 5th decrees relating to the rights of revision, the council of Sardica endeavoured to settle the procedure of ecclesiastical appeals.