CHRONOLOGY

-GENERAL The human notion of time involves the simultaneous and successive occurrence of events; the science of chronology ascertains their proper sequence. The human idea of time also involves measuring; chronology, therefore, attempts to determine the duration of past events, the amount of time between events, and the distance between past events and our time, measured in regular astronomical units: days, years, etc. Thus chronology attempts to locate an event relatively with respect to other events, and absolutely in terms of the present system of reckoning dates. Relative Dating ARCHAEOLOGY In an archaeological excavation several layers of habitation may be uncovered, those nearest to the surface being the most recent. Pottery specimens (especially good evidence because of their virtual indestructibility and therefore useful as a scale for relative dating in archaeology) may be found in each stratum, and a relative sequence of pottery styles can be established. Another way of establishing such a sequence is through finds in different sites whose relative chronology is known from another source, e.g., Greek colonies in Italy whose order of foundation is given by Thucydides. Once this stylistic, or typological, sequence is established, it is possible to determine the place in that sequence for other materials found in close association with one of the known pottery styles. Paleography, the study of ancient modes of writing and alphabet forms, can often give relative dates for undated documents. Where evidence is abundant, e.g., epigraphic Athenian decrees or Greco-Roman papyri from Egypt, literary analysis – particular usage of language, especially technical terms or legal formulas – can be valuable for approximate dating. NUMBERED AND NAMED YEARS Ancient Near Eastern historical records such as king lists and annals furnish sequences of rulers, the number of years in a king's reign, and, in the case of annals and some monuments, events assigned to numbered regnal years. In counting years the historian must know when the first regnal year began. In Egypt the interval between a king's accession and the subsequent new year was his first regnal year; but in Babylon that period was called "the beginning of the reign," while the counting of regnal years commenced only after the new year. In certain countries years were named after important events, as in ancient Mesopotamia, or after "eponymous" magistrates of whom there are some extant lists, e.g., limmu in Assyria, archon in Athens (in the histories of Diodorus and Dionysius of Halicarnassus), and consul in republican Rome (in the fasti Capitolini). References to contemporary persons or events in ancient documents are helpful in establishing more accurate sequences, or in relating two known sequences to each other. An example is the so-called "Synchronistic Chronicle," an Assyrian document listing Assyrian monarchs and contemporary Babylonian kings. More sophisticated synchronisms are found in the works of historians like Diodorus, who prefaces each annual account with the year's Athenian archon, Roman consul, and, if appropriate, Olympiad. The historian who works with these materials faces a variety of problems. Lists of kings and eponymous officials are often schematic and inaccurate, especially for early periods. Mesopotamian king lists, for example, are not reliable for the first part of the second millennium B.C.E., while Manetho's list of Egyptian pharaohs is reliable for the New Kingdom but unreliable for the First and Second Intermediate Periods, where it differs from another king list, the Turin Papyrus. Although trustworthy after around 300 B.C.E., the Roman fasti present difficulties for earlier dates. The date indicated by the fasti for the Gallic sack of Rome, for instance, differs from the date established by Polybius through synchronisms with Greek history. Contemporary, often rival, dynasties were sometimes recorded as successive in the king lists, either erroneously or because of political considerations. Some rulers were accidentally omitted from the lists or intentionally suppressed, and a king could predate his years to the beginning of a previous reign in order to strengthen his own legitimacy by refusing to recognize that of his predecessor. Editors altered their material to bring it into harmony with accepted historical traditions. Another problem for the historian is that political calendars, e.g., the Athenian and Roman, began at different times of the year, making exact synchronisms difficult. Absolute Dating Where hypothetical sequences have been established, the dating still remains relative until an absolute date for at least one unit in the sequence is known. This is true for pottery, written documents, such as the Dead Sea Scrolls, and king or eponym lists. The goal of chronology is to date objects or events accurately according to our calendar (the Julian, see below).   A physical process known as radiocarbon dating, devised by W.F. Libby, is a direct method of determining approximately the absolute date of an ancient object. In living organisms, a certain organic proportion of the carbon is carbon 14, i.e., "heavy," or radioactive carbon, which, after death, disintegrates at a constant rate. In substances of organic origin, therefore, approximate dates can be calculated from the extent to which the ratio of carbon 14 to carbon 12 (the normal, non-radioactive variety) has fallen. This radiocarbon method is especially useful for dating prehistoric discoveries, e.g., organic (wooden) objects from the pre-urban civilizations of Mesopotamia. Dates, however, can be given only with wide margins of error, extending to centuries. The most accurate keys for reduction to absolute dates are references to astronomical events, which modern science can pinpoint to exact calendar dates. For example, the entire series of Assyrian limmu (successive eponyms) from 911 to 648 B.C.E. can be dated by means of an eclipse which occurred in 763 B.C.E. Celestial phenomena, however, are cyclical; so the approximate date of the recorded event must be known before this method can be used. The historical method of arriving at absolute dates is based on the fact that our reckoning of years continues (with slight modifications, see below) to be according to the Julian calendar. From a fixed point – the Christian Era – we can count forward or backward by Julian years and months to get an exact date. Thus all non-Julian, even Roman pre-Julian dates, must be converted into Julian ones before they can be made absolute. Several factors, however, make this task difficult. Counting backward would be easier if we possessed a sufficient number of ancient systems of enumerating years. However, before the Seleucids, who used the date of the accession of their dynasty (312/311 B.C.E.; see below) as the key for calculating the years, such systems are nonexistent. Later eras also marked accessions (e.g., that of Diocletian, 284 C.E.), victories (e.g., that of Actium, 31 B.C.E.), or the establishment of a Roman province (e.g., Macedonia, 148 B.C.E.). None of these, of course, is of help for pre-Seleucid dates. Other related systems are the counting of Olympiads (every four years from 776 B.C.E.), Roman reckoning ab urbe condita ("from the founding of the city," in 753 B.C.E.), the Jewish "Era of Creation" (Anno Mundi, from 3761 B.C.E.; see below), and the Christian Era, devised by Dionysius Exiguus 532 years after the Incarnation. These, however, are the reckonings of chronographers, and were not officially used as designations for years. CALENDARS Another factor which makes absolute dating difficult, even where a dated document is extant, is the great variation among ancient calendar systems. Widespread in the Near East and Greece was the lunisolar year, a system of twelve annual lunar months made to correspond with the solar year, by means of periodic intercalation. Determination of the calendar evolved from declaring the beginning of each month upon the sighting of the first crescent of the new moon to the more sophisticated cyclical calculation of new moons and intercalations. The basic Babylonian scheme was adopted by the Jews (who did not, however, abandon lunar observation for calculation until the fourth century C.E.), the Persians, and later the Seleucids (who retained the Macedonian names of the months). Greek calendars were theoretically lunisolar, but alternated "full" (30 days) with "hollow" (29 days) months. These were somewhat artificial calendars, according to which festivals were held, and they did not necessarily correspond to the actual lunar cycles. lntercalations and other adjustments were made arbitrarily when deemed necessary, even for political reasons. In Athens, there was in addition to the civil lunisolar calendar the political Prytany calendar, which divided the year into administrative periods. This artificiality and, furthermore, the lack of uniformity between the calendars of different Greek cities, makes it extremely difficult to establish a correct Julian date; the historian considers himself fortunate when he is able to determine the correct Julian year and season of an event in Greek history. The Macedonian calendar used by the Ptolemies for official purposes was lunisolar; but by the end of the third century B.C.E. it was adjusted to fit the ancient standard Egyptian year, a uniform and completely solar year of 365 (12 × 30 + 5) days. The early Roman calendar of 355 days with intercalations every second year also ignored the moon. Julius Caesar abandoned the old system and instituted the nearly astronomically correct year of 365¼ days, which agreed with the sun and the seasons. The modern calendar is this Julian calendar (used regularly from 8 C.E.) adjusted by Pope Gregory XIII: ten days were dropped in 1582 and the quadrennial intercalary day is to be omitted in three years out of every 400 (i.e., it was omitted in 1700, 1800, and 1900, but not in 2000). It must be noted that although the various official calendars may aid the modern historian, the ancient peasant probably reckoned time according to the "natural" year, i.e., by the seasons, stars, and certain constellations like the signs of the zodiac. CHRONOGRAPHY Hellanicus of Lesbos was the first to adjust the dates of events to a common standard, the year of the priestesses of Hera at Argos. Timaeus and Eratosthenes dated by Olympiads. Eratosthenes, the first "scientific" chronographer, also produced a scheme for dating events in Greek history by counting the number of years in the intervals between important occurrences. The "Canon" in Eusebius' Chronica (c. 300 C.E.), translated by Jerome and continued up to 378 B.C.E., has an ambitious scheme of synchronisms: years after Abraham (counted from 2016 B.C.E.), royal years, Olympiads, and so on. Theon's commentary on the astronomer Ptolemy's work (the "Ptolemaic Canon") gives astronomically exact dates for successive reigns of Babylonian, Persian, Ptolemaic, Roman, and Byzantine rulers.   Using these sources, especially Eusebius, the first modern chronographers, G. Scaliger (1540–1609) and D. Fetavius (1583–1652), calculated the ancient dates in terms of Julian years. The weakness of their systems was that they were limited in their sources to often erroneous dates furnished by the ancients themselves, and to sometimes faulty manuscript traditions which perpetuated errors. The basic method of converting dates to our own reckoning is to establish a Julian date by working back through years in the era of Diocletian and Roman consular lists. For Roman pre-Julian and Greek dates with rare exception we must be satisfied with getting the Julian year and the approximate season with the help of synchronisms. Using king lists and synchronisms for the Near East, we must still recognize a margin of error of about ten years back to the 14th century B.C.E., 50 to the 17th century, and 100 or more for earlier dates. For the pre-literate period we must resort to archaeological methods. (Stanley Isser) -JEWISH METHODS OF COUNTING In the biblical period, especially from the beginning of the Monarchy, the years were counted according to the regnal years of the Israelite and Judahite kings. There was never a fixed era, such as the classical Greek Era of the Olympiads (see above). In the Persian period (from 539 B.C.E. on), the Jews, as Persian subjects, counted according to the regnal year of the contemporary Persian monarch (e.g., Haggai 1:1; Zech. 1:1). In the Hellenistic period, the Seleucid reckoning came into use. The victory of Seleucus and his ally Ptolemy over Demetrius Poliorcetes at Gaza in 312 B.C.E. and the triumphant return of Seleucus to Babylon was taken to mark the beginning of a new era (Dec. 7, 312, in the Macedonian calendar and April 3, 311, in the Babylonian calendar). The Seleucid era was in vogue among the Jews until the Middle Ages (in the East it lasted until the 16th century). Other eras which did not last were the Hasmonean era (from the accession of simeon the hasmonean 143/2 B.C.E.), and the "Era of the Redemption of Zion" (between the years 66 and 70 and the era of "The Freedom of Israel," front 131 to 135 C.E.). Dates have also been reckoned from the destruction of the Second Temple (minyan le-ḥurban ha-bayit): year one of this era = 3830 Anno Mundi = year 381 of the Seleucid era = 69/70 C.E. The era at present in use among the Jews is the minyan la-yeẓirah, "Era of the Creation," according to which the years are calculated from the creation of the world (Anno Mundi). This era came into popular use about the ninth century C.E. In various rabbinical computations the "Era of the Creation" began in the autumn of one of the years between 3762 and 3758 B.C.E. From the 12th century C.E., however, it became accepted that the "Era of the Creation" began in 3761 B.C.E. (to be exact, on Oct. 7 of that year). This computation is founded on synchronisms of chronological elements expressed in the Bible and calculations found in early post-biblical Jewish literature. Traditional Jewish Chronography The earliest Jewish chronological works that counted the years from the Creation have not survived. Of the work by the Alexandrian Jew Demetrius (third century B.C.E.), which deduced Jewish historical dates from the Bible, only a few fragments are extant. In the book of jubilees , events from the Creation to the Exodus are dated by the cycles of jubilee and sabbatical years, i.e., cycles of 49 and seven years. Scholars differ as to the date and origin of Jubilees (see calendar ). The Era of the Creation in this work is probably only hypothetical. The earliest and most important of all the Jewish chronological works extant is the seder olam , which, according to talmudic tradition, was compiled by Yose b. Ḥalafta in the second century C.E. The author, whose date is unknown, was possibly the first to use the rabbinic "Era of the Creation." His chronology extends from the Creation to the period of Bar Kokhba, i.e., to the days of the Roman emperor Hadrian; but the period from Nehemiah to Bar Kokhba (i.e., from Artaxerxes to Hadrian) is compressed into one single chapter. The Persian phase shrinks to only 54 years (the variant reckoning of 250 years is corrupt, see seder olam ). In the Talmud Seder Olam combines an interpretation of biblical data with rabbinic tradition. According to the latter, the period of the Second Temple lasted 420 years (Av. Zar. 9a). This calculation is related to the 490 years of Daniel (Dan. 9:24), taken as the interval between the destruction of the First Temple and the destruction of the Second Temple. If 70 years are subtracted for the Exile, then a period of 420 years is left for the Second Temple. The author of Seder Olam divides this period as follows: the period of Persian rule – 34 years; the Greek period – 180 years; the Maccabees – 103 years; and the Herods – 103 years. Counting back from the destruction of the Second Temple (70 C.E.) would give the date 33 C.E. for the accession of Herod the Great, 136 B.C.E. for the Hasmonean era, and, with 180 years for the rule of the Greeks, would place Alexander the Great in the Land of Israel in the year 316 B.C.E. Before this, however, the schematic 420 years for the existence of the Second Temple leaves only 34 years from the completion of the Temple (according to our chronology 516 B.C.E.) to Alexander the Great (332 B.C.E.) instead of 184 years. In other words, a large error emerges in the Seder Olam author's calculations of the Persian period. A number of attempts have been made to reconcile the Seder Olam with accepted historical data. H. Englander has suggested that the 34 years mentioned by the tanna are not to be counted from the conquest of Babylon by Cyrus to Alexander, but from the time when the Jewish community was truly reestablished on the basis of the Torah as the fundamental law after Ezra's arrival. This interpretation would imply that the Artaxerxes of Ezra's time was the second king by that   name and that Ezra's arrival must be dated at about 398 B.C.E. The above assumptions are not the predominant view among scholars, and even if they were, they would place Alexander's arrival at 364 B.C.E. which in itself is incorrect. According to J.Z. Lauterbach, the chronological problem is the result of amoraic misunderstandings of tannaitic statements that were essentially correct. The intention of the author of Seder Olam was not to give one complete and congruous report on the period of the Second Temple. He merely assembles sundry ideas about the various governments, each one complete in itself but not connected. His statement attributing 103 years each to the Hasmonean and Herodian regimes is basically correct. The 180 years of Greek rule can also be upheld if Ptolemy's invasion of Jerusalem in 320 B.C.E. is taken as the beginning of Greek rule and the recognition of Jewish independence by the Roman senate in 139 B.C.E. as the end of Greek rule. As to the problematic 34 years of Persian rule, Lauterbach claims that the statement בפני הבית (at the time of the Temple) was not correctly understood. In reality it means לפני הבית (before the time of the Temple; there may even have been a copyist's error), and the intention was merely to state that Persian rule before the rebuilding of the Temple extended for 34 years. From Cyrus' conquest of Babylon in 549 B.C.E. until 516 B.C.E., when the Temple was completed, spans 34 years. The suggestion is ingenious but unacceptable, since Babylon fell not in 549 but in 539 B.C.E. Although Cyrus undertook the conquest of Lydia in 547–546, and large parts of Babylonian territory were conquered, Babylon itself was not. The attempt to reconcile biblical and talmudic chronology with historical data is not always successful for a number of reasons. First, despite their relative proximity to the events, the ancients did not possess the scientific and archaeological methods that enable modern scholars to arrive at far more accurate conclusions. Second, and perhaps more significant, their interest was not so much academic as religious. Tradition had to be upheld at all costs, especially in the face of dissident sectarians. A classic example of this situation is the Sefer ha-Kabbalah by Abraham ibn Daud. Until recent times, this work served as a standard textbook on Jewish history. Today, however, the work is recognized as virtually worthless as a source of information on the biblical, talmudic, and geonic periods. Its value lies mainly in the picture the author gives of the spirit of his day and of Spanish Jewry. It is quite clear from Ibn Daud's methods and chronological conclusions that he had neither the Seder Olam Rabbah or its Zuta at his disposal. The question as to what sources were available is problematic. Ibn Daud, the staunch Rabbanite defending traditional Judaism in the face of Karaite sectarianism, uses history as a polemic to prove the validity of rabbinic tradition. History, moreover, also comforts as there is consolation in its symmetry. One purpose of the study of Israel's history is to detect the hand of Divine Providence. The proof of the existence of this force is in its rhythmic working – construction, destruction, and reconstruction, "21 years passed from the beginning of the Exile until the destruction of the First Temple and 21 years from the rebuilding of the Temple to its completion." All this was decreed from heaven to occur in periods that were equal in length and therefore symmetrical. Thus according to Ibn Daud, both the First and Second Temples endured 427 years. The First Temple was built in seven years and destroyed after a siege of seven years. The Second Temple too was destroyed after seven years of subjection to Rome and rebellion against her. It is irrelevant that Ibn Daud's symmetry blatantly contradicts the chronological data contained in the Bible. The historian's task is to find the plan and rewrite the chronological facts if necessary. This approach was not Ibn Daud's invention. In the Midrash (Gen. R. 12:8) the symmetrical balance in the story of Creation is stressed. In fact parallelism and symmetry were part of the rabbinic mind. The novelty of Ibn Daud was his use of this pattern of thinking as a law of history, Jewish as well as general. -BIBLIOGRAPHY: F.K. Ginzel, Handbuch der Chronologie, 2 vols. (1906–14); R.W. Ehrlich (ed.), Chronologies in Old World Archaeology (1965); E.J. Bickerman, Chronology of the Ancient World (1968); E. Mahler, Handbuch der juedischen Chronologie (1916; repr. 1967); H. Englander, in: Journal of Jewish Lore and Philosophy, 1 (1919), 83–103; G.F. Moore, Judaism, 1 (1927), 5–7; J.Z. Lauterbach, in: PAAJR, 5 (1934), 77–84; A.A. Akavia, Ha-Lu'aḥ ve-Shimmusho be-Khronologyah (1953); H. Tadmor in: World History Of the Jewish People (ed. by B. Mazar), 2 (1970), 63–101; E. Frank, Talmudic and Rabbinical Chronology (1956).