According to the New Catholic Encyclopedia, celebrating Christmas was first mentioned "in the Chronograph of Philocalus, a Roman almanac whose source material can be dated to 336 [C.E.]."
Ngokusho kwe-New Catholic Encyclopedia, indaba yokugujwa kukaKhisimusi yaqala ukuvela encwadini "i-Chronograph kaPhilocalus owayengumRoma, okubonakala sengathi yayibhalwe izinto zango-336 [C.E.]."