chronologia

CHRONOLOG´IA(χρονολογία) is the science by which time is measured according to the courses of the stars, and more especially of the sun and moon; but in the more limited sense in which we have to treat of chronology here, it is a part of history, and teaches us to assign each historical event to the date to which it belongs. The reduction of any given date in antiquity to the corresponding year, month, or day, in our modern computation of time, is sometimes a matter of great difficulty, and often of absolute impossibility; for nearly all the nations of antiquity began their year at a different time, some used solar and others lunar years, and others again a combination of the two; nearly all, moreover, had different eras, that is, points of time from which subsequent and preceding years are counted; and in addition to this there occur a great many changes and fluctuations in one and the same nation; and the historians whose works have come down to us are not always very precise in marking the time to which the events belong, so that we must have recourse to all manner of combinations, or are left to conjectures.

For the manner in which the Greeks and Romans calculated their years and months we refer to the article CALENDARIUMand we shall here confine ourselves to an account of the manner in which those nations calculated and stated the events of their history. The Greeks reckoned their years generally according to their magistrates, in the early times according to the years of the reign of their kings, and afterwards according to their annual magistrates. At Athens the year was called by the name of one of the nine archons, who from this circumstance was called ἄρχων ἐπώνυμος or the archon par excellence; and at Sparta the years were called after one of the five ephors, who for this reason was likewise termed ἐπώνυμος. (Thucyd. 2.2; Xenoph. Anab. 2.3.10; Plb. 12.12; Paus. 3.11.2.) But the years of the Athenian archons and the Spartan ephors, coinciding with the civil year in those states, did not coincide with each other, for the ephors entered upon their office in the Attic month of Boëdromion, while the archons originally entered upon theirs in the beginning of Gamelion, and ever since the year B.C. 490, at the beginning of Hecatombaeon. In Argos time was counted according to the years of the high priestess of Hera, who held her office for life (ἡρεσίς: Thucyd. 2.2; Suid. s. v. Ἡρεσίδες); and the inhabitants of Elis probably reckoned according to the Olympic games, which were celebrated every fifth year during the first full moon which followed after the summer solstice. In this manner every Greek state or city calculated time according to its own peculiar or local era, and there was no era which was used by all the Greeks in common for the ordinary purposes of life. Historians, therefore, down to the middle of the third century B.C., frequently made use of the average age attained by men, in order to fix the time in a manner intelligible to all Greeks. Herodotus (Hdt. 2.142) calculates that three generations of men are equivalent to a century (saeculum is sometimes so used in Latin, but not aetas). Timaeus, who flourished about B.C. 260, was the first historian who counted the years by Olympiads, each of which contained four years. The beginning of the Olympiads is universally fixed in the year 3938 of the Julian period (a cycle suggested by Joseph Scaliger, which commences B.C. 4714), or in B.C. 776. If we want to reduce any given Olympiad to years before Christ, e.q. Ol. 87, we take the number of the Olympiads actually elapsed,--that is, 86,--multiply it by 4, and deduct the number obtained from 776, so that the first year of the 87th Ol. will be the same as the year 432 B.C. If the number of Olympiads amounts to more than 776 years,--that is, if the Olympiad falls after the birth of Christ,--the process is the same as before; but from the sum obtained by multiplying the Olympiads by 4, we must deduct the number 776, and what remains is the number of the years after Christ. This calculation according to Olympiads, however, does not seem to have been ever applied to the ordinary business of life, but to have been confined to literature, and more especially to history. Some writers also adopted the Trojan era, the fall of Troy being placed by Eratosthenes and those who adopted this era, in the year B.C. 1184. After the time of Alexander the Great, several other eras were introduced in the kingdoms that arose out of his empire. The first was the Philippic era, sometimes also called the era of Alexander or the era of Edessa; it began on the 12th of November B.C. 324, the date of the accession of Philip Arrhidaeus. The second was the era of the Seleucidae, beginning on the 1st of October B.C. 312, the date of the victory of Seleucus Nicator at Gaza, and of his re-conquest of Babylonia. This era was used very extensively in the East. The Chaldaean era differed from it only by six months, beginning in the spring of B.C. 311. Lastly, the eras of Antioch, of which there were three, but the one most commonly used began in November B.C. 49. In Europe none was so generally adopted, at least in literature, as the era of the Olympiads; and as the Olympic games were celebrated 293 times, we have 293 Olympic cycles, that is, 1172 years, 776 of which fall before and 396 after Christ. But when the Greeks adopted Christianity, they probably ceased to reckon by Olympiads, and adopted the Julian year. The practice of dating from the birth of Christ was introduced by Dionysius Exiguus in A.D. 532. (Corsini, Fasti Attici, Florence, 1744-56, 4 vols. 4to; Ideler, Handbuchder mathem, und technisch. Chronol. Berlin, 1825, 2 vols. 8vo; Clinton, Fasti Hellenici, Oxford, 1830-1834, 3 vols. 4to.)

The Romans in the earliest times counted their years by their highest magistrates, and from the time of the republic according to their consuls, whose names were registered in the Fasti. This era, which may be termed the aera consularis, however did not begin at all times at the same point; for in the earliest times of the republic the consuls entered upon their office on the calendae of Sextilis, at the time of the decemvirate on the ides of May, afterwards on the ides of December, and at a still later time on the ides of March, until in B.C. 153 the consuls began regularly to enter upon their office on the 1st of January. This constant shifting was undoubtedly one of the causes that produced the confusion in the consular era, of which Livy (Liv. 2.18, 21, &c.) complains. Great confusion also arose from the incompleteness or the deliberate falsification of the records, and the interruption caused by interregna, so that it is quite impossible to draw up satisfactory Fasti Consulares. (Cf. C.I. L. 1.403-551, with Mommsen's important commentary.) Varro, Cicero, Tacitus, and even Gaius, date events by the number of years which had elapsed since the expulsion of the kings. The earliest use of a fixed point from which to date is in the dedication of the Temple of Concord by Cn. Flavius, cciii. annis post Capitolinam dedicatam (Plin. Nat.33.19). The consular era was the one commonly used by the Romans for all practical purposes, the date of an event being marked by the names of the consuls, in whose year of office it had happened. But along with this era there existed another, which as it was never introduced into the affairs of common life, and was used only by the historians, may be termed the historical era. We have no instance of the use of this era at Rome before the time of Augustus ; but in the case of other Italian towns a similar practice was employed much earlier (Plin. Nat.3.114.) It reckoned the years from the foundation of the city (ab urbe condita); but the year of the foundation of the city was a question of uncertainty among the Romans themselves, although all agreed in the day of the month, i. e. April 21st, the Parilia (Dionys. 1.88). M. Terentius Varro and Atticus placed it in the third year of the 6th Olympiad, that is, B.C. 753. (Plut. Rom. 12; Vellei. 1.8; Censorin. de Die Nat. 17.) This era was adopted by Velleius Paterculus, Pliny, Tacitus, A. Gellius, Dio Cassius, Eutropius, and others. Next to the Varronian era, the most celebrated was that of M. Porcius Cato, who placed the foundation of Rome in the first year of the 7th Olympiad, or in the spring of B.C. 751. (Dionys. 1.74; Syncell. Chronog. p. 194 a.) The date fixed upon in the aera Capitolina (so called from the Fasti Capitolini), by Polybius (Dionys. l. c.; Cic. de Rep. 2.10), Diodorus, and Cornelius Nepos, was one year later; Q. Fabius Pictor placed the foundation in the first year of the 8th Olympiad, i. e. 747 B.C. (Dionys. l. c.), and Cincius Alimentus even placed it about the fourth year of the 12th Olympiad, i. e. B.C. 729. Ennius, on the other hand, placed the building of Rome about 700 years before his own time; that is, at least 100 years earlier than most other writers (Varro, de Re Rust. 3.1); and Timaeus went so far as to regard the foundation of Rome contemporaneous with that of Carthage, placing it 38 years before the first Olympiad. But no reliance can be placed on any of these statements; as however it is necessary to have one point to start from, the Varronian era has been adopted by modern writers.

(χρονολογία). See calendarium.