Indiction

INDICTION. - A chronological computation based on a fifteen-year cycle whose years are numbered progressively from 1 to 15 and designated respectively as indiction I, II, III, etc. After indiction XV the numbering begins again from 1, always limiting itself to mentioning the year of each cycle and disregarding any indication relating to the series of cycles themselves. The indiction is therefore not in itself a sufficient chronological indication, but must be related to other dates (Christian era, years of reign or of pontificate, etc.): it does, however, constitute an element of control and is of great importance in diplomatic criticism.

Its use goes back, in Egypt, at least to A.D. 29 (cf. A. Calderini, Papyri, Milan [1944], p. 35 ff.); it seems that the indictional period corresponded, in that region, to the span of time elapsing between one cadastral revision and the next; the computation would have been introduced at first in documents relating to tax impositions and from there would have spread to other acts: having penetrated into liturgical practice, its use became general.

The indictional year, like the year of the Christian era, did not begin everywhere on the same day, so that in checking one must take into account the possibility that the indictional figure turns out to be increased or decreased by one unit according to the style followed in that era and in that region. The following were in use: a) the Greek, or Constantinopolitan, indiction, beginning on 1 September, which therefore anticipates the year of the circumcision by 4 months: it was proper to the court of Byzantium, used by preference in pontifical documents from Pelagius II to Victor III, employed in royal documents until 832, and very widespread in public and private acts of southern Italy; b) the Bedan indiction, so called by Grotefend because it is first attested in St. Bede, also improperly called Caesarean or Constantinian, beginning on 24 September, which anticipates the year of the circumcision by 3 months and 6 days: it is found in the imperial chancery until 850, variously in Italy, especially central Italy, and is widely diffused in episcopal documents of Germany until the middle of the 14th century. In the territory of Genoa it is encountered with a delay of one year, that is, with one unit less than the common Bedan computation; c) the Roman or pontifical indiction, beginning on 25 December, and then on 1 January, coinciding therefore with the year of the nativity first, and with that of the circumcision afterwards; it is attested in Rome at the end of the 10th century; from 1088 its use begins in pontifical letters, and with the 13th century it is also encountered in the German chancery; it then becomes of general use and today is the only one that survives in the liturgy; d) the Sienese indiction, beginning on 8 September, and in advance by 3 months and 22 days of the year of the circumcision; limited in use to the territory of Siena, it is always found in synchrony with the year ab incarnatione in the Florentine style.

Starting from the earliest documentary evidence on the use of the indiction, it has been calculated hypothetically that the year 1

A.D. would correspond to indiction IV, that is, that the beginning of the Christian era is three years behind the beginning of an indictional cycle: «Quarta indictione secundum Dionysium natus est Dominus» (Bede, De temporum ratione, 49: PL 90, 496). From this observation one has worked back to the formulation of the rule for calculating the indiction, which is obtained by adding 3 units to the figure of the year of the Christian era and dividing the sum by 15: the remainder gives the indiction (a remainder of zero corresponds to indiction XV), while the quotient, which has no importance for the purposes of chronological calculation, represents the hypothetical figure of the indictional cycles from the beginning of the common era to the date on which the calculation is performed.

Alessandro Pratesi