Babylonian Chronology. Babylon enters the Biblical picture principally from the time of Nebuchadnezzar II onward. The reign of Nebuchadnezzar’s father Nabopolassar marked the start of what is called the Neo-Babylonian Empire; it ended with the reigns of Nabonidus and his son Belshazzar and the overthrow of Babylon by Cyrus the Persian. This period is of great interest to Bible scholars since it embraces the time of the Babylonian destruction of Jerusalem and the greater part of the 70-year period of Jewish exile.

Jeremiah 52:28 says that in the seventh year of Nebuchadnezzar (or Nebuchadrezzar) the first group of Jewish exiles was taken to Babylon. In harmony with this, a cuneiform inscription of the Babylonian Chronicle (British Museum 21946) states: “The seventh year: In the month Kislev the king of Akkad mustered his army and marched to Hattu. He encamped against the city of Judah and on the second day of the month Adar he captured the city (and) seized (its) king [Jehoiachin]. A king of his own choice [Zedekiah] he appointed in the city (and) taking the vast tribute he brought it into Babylon.” (Assyrian and Babylonian Chronicles, by A. K. Grayson, 1975, p. 102; compare 2Ki 24:1-17; 2Ch 36:5-10.) (PICTURE, Vol. 2, p. 326) For the final 32 years of Nebuchadnezzar’s reign, there are no historical records of the chronicle type except a fragmentary inscription of a campaign against Egypt in Nebuchadnezzar’s 37th year.

For Awil-Marduk (Evil-merodach, 2Ki 25:27, 28), tablets dated up to his second year of rule have been found. For Neriglissar, considered to be the successor of Awil-Marduk, contract tablets are known dated to his fourth year.

A Babylonian clay tablet is helpful for connecting Babylonian chronology with Biblical chronology. This tablet contains the following astronomical information for the seventh year of Cambyses II son of Cyrus II: “Year 7, Tammuz, night of the 14th, 1 2⁄3 double hours [three hours and twenty minutes] after night came, a lunar eclipse; visible in its full course; it reached over the northern half disc [of the moon]. Tebet, night of the 14th, two and a half double hours [five hours] at night before morning [in the latter part of the night], the disc of the moon was eclipsed; the whole course visible; over the southern and northern part the eclipse reached.” (Inschriften von Cambyses, König von Babylon, by J. N. Strassmaier, Leipzig, 1890, No. 400, lines 45-48; Sternkunde und Sterndienst in Babel, by F. X. Kugler, Münster, 1907, Vol. I, pp. 70, 71) These two lunar eclipses can evidently be identified with the lunar eclipses that were visible at Babylon on July 16, 523 B.C.E., and on January 10, 522 B.C.E. (Oppolzer’s Canon of Eclipses, translated by O. Gingerich, 1962, p. 335) Thus, this tablet points to the spring of 523 B.C.E. as the beginning of the seventh year of Cambyses II.

Since the seventh year of Cambyses II began in spring of 523 B.C.E., his first year of rule was 529 B.C.E. and his accession year, and the last year of Cyrus II as king of Babylon, was 530 B.C.E. The latest tablet dated in the reign of Cyrus II is from the 5th month, 23rd day of his 9th year. (Babylonian Chronology, 626 B.C.–A.D. 75, by R. Parker and W. Dubberstein, 1971, p. 14) As the ninth year of Cyrus II as king of Babylon was 530 B.C.E., his first year according to that reckoning was 538 B.C.E. and his accession year was 539 B.C.E.

Berossus. In the third century B.C.E. Berossus, a Babylonian priest, wrote a history of Babylon in the Greek language, evidently based on cuneiform records. Of his writings, Professor Olmstead said: “Only the merest fragments, abstracts, or traces, have come down to us. And the most important of these fragments have come down through a tradition almost without parallel. Today we must consult a modern Latin translation of an Armenian translation of the lost Greek original of the Chronicle of Eusebius, who borrowed in part from Alexander Polyhistor who borrowed from Berossus direct, in part from Abydenus who apparently borrowed from Juba who borrowed from Alexander Polyhistor and so from Berossus. To make a worse confusion, Eusebius has in some cases not recognized the fact that Abydenus is only a feeble echo of Polyhistor, and has quoted the accounts of each side by side! And this is not the worst. Although his Polyhistor account is in general to be preferred, Eusebius seems to have used a poor manuscript of that author.” (Assyrian Historiography, pp. 62, 63) Josephus, Jewish historian of the first century C.E., also claims that he quotes from Berossus. But it seems evident that chronological data supposedly from Berossus could hardly be considered conclusive.

Other factors allowing for differences. Casual students of ancient history often labor under the misconception that the cuneiform tablets (such as may have been used by Berossus) were always written at the same time or shortly after the events recorded on them. But, aside from the many cuneiform business documents that were truly contemporary, the Babylonian historical texts and even many astronomical texts often give evidence of being of a much later period. Thus, according to Assyriologist D. J. Wiseman, one portion of the so-called Babylonian Chronicle, covering the period from the rule of Nabu-nasir to Shamash-shum-u-kin (a period dated by secular historians as from 747-648 B.C.E.), is “a copy made in the twenty-second year of Darius [footnote says: I.e. 500/499 B.C. if Darius I] from an older and damaged text.” (Chronicles of Chaldaean Kings, London, 1956, p. 1) So, not only was this writing separated from the events recorded on it by anywhere from 150 to 250 years but it was also a copy of a defective earlier document, perhaps an original, perhaps not. Of the Neo-Babylonian Chronicle texts, covering the period from Nabopolassar to Nabonidus, the same author states: “The Neo-Babylonian Chronicle texts are written in a small script of a type which does not of itself allow any precise dating but which can mean that they were written from any time almost contemporary with the events themselves to the end of the Achaemenid rule.” This allows for the possibility that they were written as late as the close of the Persian Empire, which occurred in 331 B.C.E. some 200 years after the fall of Babylon. We have already seen that data, including numbers, can easily suffer change and even perversion at the hands of pagan scribes in the course of a few centuries. In view of all these factors it is certainly not wise to insist that the traditional figures for the reigns of the Neo-Babylonian kings be received as definite.

Both the lack of contemporary historical records and the ease with which data could be altered definitely allow for the possibility that one or more of the Neo-Babylonian rulers had a longer reign than the traditional figures show. The fact that no tablets have been discovered that would cover the later years of such reign cannot consistently be used as a strong argument against this possibility. There are cases of kings whose reigns come much farther along in the stream of time and for whom no such confirming tablets have been found. For example, for both Artaxerxes III (Ochus) (who, historians say, ruled for 21 years [358 to 338 B.C.E.]) and Arses (credited with a 2-year rule [337 to 336 B.C.E.]) there is no known contemporary cuneiform evidence to help establish the length of their reigns.

In reality, historians do not know where to place certain Babylonian kings for whom records do exist. Professor A. W. Ahl (Outline of Persian History, 1922, p. 84) states: “On the Contract Tablets, found in Borsippa, appear the names of Babylonian kings which do not occur elsewhere. In all probability they belong to the last days of Darius I, extending into the first days of Xerxes I, as Ungnad conjectures.” Still, this remains only conjecture.

Ptolemy’s canon. Claudius Ptolemy was a Greek astronomer who lived in the second century C.E., or over 600 years after the close of the Neo-Babylonian period. His canon, or list of kings, was connected with a work on astronomy that he produced. Most modern historians accept Ptolemy’s information about the Neo-Babylonian kings and the length of their reigns.

Evidently Ptolemy based his historical information on sources dating from the Seleucid period, which began more than 250 years after Cyrus captured Babylon. It thus is not surprising that Ptolemy’s figures agree with those of Berossus, a Babylonian priest of the Seleucid period.

Lunar eclipses. These have been used to try to substantiate the dates given for particular years of the Neo-Babylonian kings on the basis of Ptolemy’s canon and data in the cuneiform records. But even though Ptolemy may have calculated accurately or recorded the dates of certain eclipses in the past (a modern astronomer found three fifths of Ptolemy’s dates correct), this does not prove that his transmission of historical data is correct, that is, that his correlation of eclipses with the reigns of certain kings is consistently based on true historical fact.

Not all the texts historians use to date events and periods of ancient history are based on eclipses, however. Astronomical diaries have been found that give the position (in relation to certain stars or constellations) of the moon at its first and last visibility on a specific day in Babylon (for example, “the moon was one cubit in front of the rear foot of the lion”), along with the positions of certain of the planets at these same times. Modern chronologers point out that such a combination of astronomical positions would not be duplicated again in thousands of years. These astronomical diaries contain references to the reigns of certain kings and appear to coincide with the figures given in Ptolemy’s canon. While to some this might seem like incontrovertible evidence, there are factors greatly reducing its strength.

The first is that the observations made in Babylon may have contained errors. The Babylonian astronomers showed greatest concern for celestial events or phenomena occurring close to the horizon, at the rising or setting of the moon or of the sun. However, the horizon as viewed from Babylon is frequently obscured by sandstorms. Commenting on these factors, Professor O. Neugebauer states that Ptolemy complained about “the lack of reliable planetary observations [from ancient Babylon]. He [Ptolemy] remarks that the old observations were made with little competence, because they were concerned with appearances and disappearances and with stationary points, phenomena which by their very nature are very difficult to observe.”​—The Exact Sciences in Antiquity, 1957, p. 98.

Second, the fact is that the great majority of the astronomical diaries found were written, not in the time of the Neo-Babylonian or Persian empires, but in the Seleucid period (312-65 B.C.E.), although they contain data relating to those earlier periods. Historians assume that they are copies of earlier documents. Actually contemporaneous astronomical texts are lacking by which to establish the full chronology of the Neo-Babylonian and Persian periods (late seventh to late fourth centuries).

Finally, as in the case of Ptolemy, even though the astronomical information (as now interpreted and understood) on the texts discovered is basically accurate, this does not prove that the historical information accompanying it is accurate. Even as Ptolemy used the reigns of ancient kings (as he understood them) simply as a framework in which to place his astronomical data, so too, the writers (or copyists) of the astronomical texts of the Seleucid period may have simply inserted in their astronomical texts what was then the accepted, or “popular,” chronology of that time. That accepted, or popular, chronology may well have contained errors at the critical points dealt with earlier in this article. To illustrate, an ancient astronomer (or a scribe) might state that a certain celestial event took place in the year that, according to our calendar, would be 465 B.C.E., and his statement may prove correct when accurate computations are made to verify it. But he may also state that the year in which the celestial event took place (465 B.C.E.) was the 21st year of King Xerxes and be entirely wrong. Simply stated, accuracy in astronomy does not prove accuracy in history.