It would have been written Prid. Kal. Ian. DCCLIII. The Romans counted there era from the supposed date of the foundation of the city of Rome; the year here would be 753 years after that date. Prid. is the abbreviation of the Latin pridie for ' on the day before' and Kal. is for Kalends which were the 1st of the month, one of the three set days in a month to which dates were counted ( the others were nones and ides ). Ian. is for Ianuarius, January . The date is therefore the day before the kalends of January. They would not normally have bothered but they would formally write A U C ( ab urbe condita 'from the founding of the City) after the year, not BC or BCE.