http://en.wikipedia.org/wiki/Quartodecimanism
Christians in the churches of Jerusalem and Antioch in the Roman province of Asia (Western Anatolia) celebrated Passover on the 14th of the first month (Aviv)
In the mid–second century, the practice in the Roman province of Asia was for the pre-Paschal fast to end and the feast to be held on the 14th day (the full moon) of the Jewish lunar month of Nisan, the date on which the Passover sacrifice had been offered when the Second Temple stood, and "the day when the people put away the leaven".[5] Those who observed this practice were called Quartodecimani, Latin for "fourteenthers", because of holding their celebration on the fourteenth day of Nisan.
The practice had been followed by Polycarp, who was a disciple of John the Apostle and bishop of Smyrna (c. 69 – c. 155) - one of the seven churches of Asia, and by Melito of Sardis (d. c. 180).[5] Irenaeus says that Polycarp visited Rome when Anicetus was its bishop (c. 153–68), and among the topics discussed was this divergence of custom, with Rome instituting the festival of Easter in place of the Pasch. Irenaeus noted:
Neither could Anicetus persuade Polycarp not to observe what he had always observed with John the disciple of our Lord, and the other apostles with whom he had associated; neither could Polycarp persuade Anicetus to observe it, as he said that he ought to follow the customs of the presbyters that had preceded him.[6]