Indiction

Indiction, a period or cycle of fifteen years, the origin of which is involved in obscurity, but which was originally a fiscal term. It began to be used in reckoning time, chiefly by ecclesiastical historians, during the life of Athanasius; it was afterwards adopted by the popes, who still continue to use it, and through whose influence it came to be so generally employed during the middle ages that the dates of charters and public deeds of this era are expressed in indictions as well as in years of the Christian era. The first indiction is supposed to have commenced on September 24, 312, the day of Constantine's victory over Maxentius. If we reckon backwards to the commencement of the Christian era it will be seen that 1 A.D. does not correspond to the 1st, but to the 4th year of an indiction—hence, if to any given year of the Christian era 3 be added, and the sum divided by 15, the remainder will give the position of that year in an indiction—thus, 1890 A.D. was the third year of an indiction. Of course such a method of marking time was necessarily incomplete, for it included no statement of the number of indictions which had elapsed since the first adoption of that method of computation.