» Chronology

Introduction

Chronology

Chronology is always a thorny subject, and dry and unsatisfactory to most persons beside; some notice, however, must be taken of it here…
George Smith, The Chaldean Account of Genesis, 1876

Chronology is the bones of history. Although dry and unsatisfactory at first, the chronology of the ancient world presents many intriguing puzzles. But for the student opening a history textbook for the first time, it probably seems as though the dates assigned to the ancient world are mostly fixed and that there is nothing left to do except memorize the tables. Not so! Many hotly contested historical questions center on questions of chronology. We will touch on several of these in this course.

The Three-Age System

The Greek poet, Hesiod (7^th century BC), was the first to divide history into metallic ages. He used them to tell a story about the movement of human civilization through successive ages of gold, silver, and bronze until arriving finally at his own strife-filled age—the age of iron. Hesiod’s parable alludes to the various metals which were known and used in each period but he was more interested in making a philosophical argument than a historical one. It wasn’t until the early 1800’s that the Danish archaeologist, Christian Jürgensen Thomsen, began to organize the artifacts in his museum according to three broad periods, which he named after the materials utilized in each of them: stone, bronze, and iron. The “Three-Age” system, as it came to be known, has proven to be a useful historical framework even though, as we will see, reality is quite a bit more complicated than this system implies.¹ Although the focus of this course is on the Early Bronze period, it will be helpful to familiarize yourself with the following historical periods. (All you need to know for now is the name of the period and their relative order.)

Period	Standard Chronology	Ancient List Chronology	Comments
Stone Ages	3 mya - 4500 BC	? - 3500(?) BC	Franchthi and Shanidar Caves Hassuna, Halaf, and Samarra cultures (Syria and Mesopotamia) Ubaid culture (Mesopotamia) Yarmukian culture (Southern Levant) Catalhoyuk (Anatolia)
Chalcolithic / Early Bronze I	4500-2900 BC	3500(?)-2700 BC	European Stone Age Predynastic—Protodynastic periods (Egypt) Uruk—Jemdet Nasr periods (Mesopotamia) Ghassulian culture (Southern Levant) Megiddo XX—XIX (Southern Levant)
Early Bronze II	2900-2700 BC	2750-2500 BC	Early Dynastic I - II (Mesopotamia) Early Dynastic (Egypt) Megiddo XVIII
Early Bronze III	2700-2300 BC	2600-2200 BC	Early Dynastic III (Mesopotamia) Dynasties III-V (Egypt) Megiddo XVII - XV (Southern Levant) Mari (City II) and Ebla (Mardikh IIB1)
Early Bronze IV	2300-2150 BC	2200-2060 BC	Akkadian Period (Mesopotamia) Egyptian Dynasty VI (Late Old Kingdom) Mature Harappan period (Indus Valley) Qala'at al-Bahrain City II (Persian Gulf)
Middle Bronze I	2100-2000 BC	2060-1900 BC	Guti, Lagash II, and Ur III periods (Mesopotamia) Egyptian First Intermediate Jericho Shaft Tombs Megiddo Stratum XIV
Middle Bronze II-III	2000-1550 BC	1900-1550 BC	Rise of Amorite city-states (Canaan and Syria) Dynasty XII (Egypt) Old Babylonian Period (Mesopotamia) Middle Minoan (Aegean) Hyksos Dynasty XV - XVI (Egypt)
Late Bronze I	1550-1400 BC	-	Expulsion of the Hyksos marks beginning of the Eighteenth Dynasty Kassites control Mesopotamia
Late Bronze II	1400-1200 BC	-	Conquest of Canaan by the Israelite tribes Akhenaten moves capitol to Amarna Reign of Seti I marks beginning of Nineteenth Dynasty in Egypt Battle of Kadesh between Hittites and Egyptians Period ends in some kind of catastrophe and invasion of the Sea Peoples
Iron Age I	1200-1050 BC	-	Arrival of sea peoples from the West The Assyrians begin to consolidate power in Mesopotamia The period of the Judges in the Bible which ends with the defeat of Saul and Jonathan by the Philistines
Iron Age II	1050-586 BC	-	Rise of a united Israelite kingdom under David and Solomon Reign of Tiglath Pileser III marks beginning of Assyrian expansion Phoenicians and Greeks vie for control of Mediterranean Period ends with the destruction of Jerusalem by Nebuchadnezzar, king of Babylon
Babylonian	586-539 BC	-	Period ends with the conquest of Babylon by Cyrus the Great
Persian and Greek Period	539-333 BC	-	Period end with the defeat of Darius III at the Battle of Issus by the forces of Alexander the Great
Hellenistic Period	333-31 BC	-	Period ends with the conquest of Ptolemaic Egypt by the forces of Octavian and Marcus Agrippa
Roman Period	31 BC - 476 AD		Period ends with the deposition of the last Roman emperor in 476 AD

Calendars

All of the dates given in this course are based on the Gregorian calendar, established in 1582 by Pope Gregory XIII. That this calendar fulfills its function admirably may be gauged by the fact that if you and I arrange to meet at our favorite breakfast place on January 5th, 2054, each of us may may wonder whether we will still be alive then, or whether the restaurant will still be there, but neither of us will be in any doubt as to which day it is. Ancient calendars did not enjoy such precision, either because they lacked an accurate unit of measure, a fixed point in time, or both!

1. Unit of Measure

The year is the most basic unit of measure for a functioning calendar. Most early calendars relied upon the cycles of the moon to define a year. Since twelve lunar cycles equal approximately 354 days, the lunar year rapidly fell out of sync with the actual year, measured by the revolution of the earth around the sun every 365.2422 days. To correct for the shortfall in days, an extra month was added to the calendar every three or four years (known as an “intercalary month”). The decision to insert an intercalary month had to be made by someone, usually an appointed council. This system worked well until it didn’t. There was, for example, a period in Rome’s history, known as the Year of Confusion, when Julius Caesar added 80 days to the year! Although this drastic revision created considerable chaos, the Julian calendar was an important step towards establishing the precise calendar we use today—a calendar regulated by astronomical observation and mathematics rather than imperial decree!

2. Fixed Point in Time

Of course, it does not matter how precisely one is able to measure the length of a year if one does not also have a fixed reference point by which to number the years. Many ancient calendars used as their point of reference the ascension date of the king or, in the Roman system, the election of a new consul. Thus the calendar was reset each time a new ruler came to the throne. To help alleviate confusion, the Romans began to count the years from the founding of Rome in 753 BC whereas the Greeks used the first Olympiad in 776 BC as their fixed point. The Gregorian calendar uses the birth of the Lord Jesus Christ as the fixed point, thus dividing history into two eras: BC (“Before Christ”) and AD (Latin Anno Domini, “Year of our Lord”).

The Fasti Capitolini image taken the National Museum of Rome

Cultic Calendar from the walls of the Temple of Apollo Delphinios at Miletus

Left: Known as the Fasti Capitolini, this important Roman calendar lists all of the magistrates of Rome from the founding of Rome down to Augustus. The years of their reign are numbered from Rome’s founding ab urbe condita. Right: An ancient Greek calendar which predates the destruction of Miletus by the Persians in the 5th century BC. The calendar was inscribed on the walls of the Temple of Apollo Delphinios at Miletus.

Specifying Dates and Eras

In addition to the basic division of time into BC and AD, historians also divide time into millennia, centuries, or decades. It may be helpful at this point to quickly review a few of the common ways of delineating time using numerical time divisions.

the 2nd millennium BC refers to the period between 2000 and 1000 BC
the 2nd millennium AD refer to the period between 1000 and 2000 AD
the second half of the 2nd millennium BC refers to the period between 1500 and 1000 BC
the second half of the 2nd millennium AD refers to the period between 1500 and 2000 AD
the 5th century BC refers to the period between 500 and 400 BC
the 2nd century AD refers to the period from 100 and 200 AD
the first quarter of the 5th century BC refers to the period between 500 and 475 BC
and so on and so forth

When specifying an approximate date, historians use the notation “c.” which stands for the Latin term circa “about”. Thus “c. 1450 BC” means “around 1450 BC.”

Relative vs. Absolute Dates

A relative chronology places events in proper sequence, an easy task compared to an absolute chronology, which requires a date. Scholars have resorted to various means and methods of assigning dates. One of the most important are the limmu lists kept by Assyrian scribes. These record year names with each year named after an important Assyrian official, beginning with the king himself. A number of these lists have been found, some early and some late, but none complete. However there is sufficient overlap among them that scholars have been able to compile a list of approximately 250 names, known collectively as the Assyrian Eponym Canon (Greek eponym, “named after”).

The earliest limmu lists are just a bare list of names but some of the later ones also record important events. One event in particular has proven to be of great importance for chronology—the observation of a solar eclipse in the year of Bur-Sagale.² Since solar eclipses only occur once every 250 to 360 years in a given place,³) astronomers have been able to date the eclipse observed during the reign of Bur-Sagale with pinpoint accuracy to June 15, 763 BC. The chronology of Assyria is therefore considered to be astronomically fixed, with a complete list of officials going back to 911 BC.

Using this criteria, it has been possible to date the attack of the Assyrian king, Sennacherib, on Jerusalem, to 701 BC. Since the Bible places this same event in Hezekiah’s 14th year (2 Ki. 18:13), we now have a fixed date in the Biblical chronology.⁴ Working from this fixed point, scholars have reckoned back to the reigns of David and Solomon and the initiation of the building of the temple in Jerusalem in 967 BC. This provides the springboard for establishing several more important events in Biblical history, such as the date of the Exodus and Jacob’s descent into Egypt.

Returning to the chronology of Assyria, fragments of earlier limmu lists and several Assyrian king lists have pushed back the boundaries of Assyrian chronology several hundred more years, to around 1400 BC.⁵ For earlier periods, scholars have had to rely on other types of astronomical observations, such as a set of observations of the planet Venus recorded during the reign of Ammisaduqa, one of the last rulers of Old Kingdom of Babylon. Unfortunately, the data has not produced the kind of certainty one might have hoped for, with proposals for Hammurabi’s ascension to throne of Babylon ranging anywhere between 1700 to 1550 BC.⁶ The various proposals have been classified as the High, Middle, Low, and and Ultra-Low chronologies for Mesopotamia.

Pergamon Museum

Limmu Stele —

Erected in Assur, these stones were erected to commemorate the naming of a year after an official. “Shar-pati-beli, Governor of the cities of Assur, Nasibina, Urakka”

Although we have not mentioned it yet, Ptolemy’s Canon is arguably the most important source for establishing a chronology of the ancient world. One of the great scholars of the Roman era, Claudius Ptolemy (70-161 AD) lists the names of kings and their lengths of reign, beginning with the Babylonian king, Nabononassar (747 BC) and proceeding down to his own era, thus linking the history of Babylon with Rome. Inasmuch as Ptolemy’s Canon overlaps with the Assyrian Eponym Canon, there is considerable agreement between them. Thus Ptolemy’s Canon lays the foundation, not only for Babylonian chronology, but but also supplies the date of 664 BC for the withdrawal of the Assyrians from Egypt. This date is the key to establishing an absolute chronology for Egypt. Using various king lists, astronomical observations, and a plethora of other types of data, Egyptologists generally consider the chronology of Egypt to be accurate within 10 or 20 years for the New Kingdom period (Late Bronze Age) and to within 200 years for the Old Kingdom period (Early Bronze Age).⁷ Whether this is indeed the case, especially as it touches on the chronology of the Early Bronze Age, will be saved for a future discussion in another entry.

Carbon 14 Dating

Before leaving the topic of chronology, we should mention one final method for establishing an absolute chronology that has increasingly come to be relied upon for the chronology of the Early Bronze period—C14 dating. Discovered by Willard Libby in 1949, the method promised to provide a truly scientific and objective means of establishing an absolute chronology.

Less stable than regular carbon (C12), radioactive carbon (C14) is formed in the earth’s atmosphere when a particle from outer space (cosmic radiation ) blows apart an atom in our atmosphere, releasing free particles which, although they are are not moving so fast, they are still liable to create havoc with other atoms. For instance, if a free neutron strikes a nitrogen atom, it may dislodge one of the nitrogen’s protons and add itself to the nucleus in its place. Since nitrogen by definition has 7 protons, the loss of a proton means that it ceases to be nitrogen and becomes carbon, which by definition has 6 protons. However, it is a very unstable form (isotope) of carbon due to the addition of two extra neutrons. Thus it has an atomic mass of 14 instead of 12. Whereas C12 is stable, C14 is liable to decay, and is therefore radioactive.

Formation of C14 —

C14 forms when Nitrogen loses a proton and gains a neutron. Although it has the same number of protons as C12, it has two extra neutrons, rendering it unstable and liable to decay (radioactive).

Both radioactive carbon (C14) and regular carbon (C12) are absorbed by plants through photosynthesis. Consequently, both types of carbon are are absorbed by animals that eat the plants. As long as carbon is being actively ingested by plants and animals, they will maintain a constant ratio of C14 to C12 in their bodies, which is also the ratio present in the atmosphere. However, after death the organism ceases to absorb carbon. Whereas the C12 remains, the C14 is slowly dissipated due to decay. Every 5700 years or so the amount of C14 contained in the “living thing now dead” is halved. Libby’s great insight was that, 1) if you can determine the ratio of C14 to C12 in the atmosphere when something died, and, 2) if you can measure the amount of C14 present in what remains of it, then you should theoretically be able to determine how old it is. Of course, there are some practical challenges that needed to be solved, such as the exceptionally miniscule amounts of C14 involved. The ratio of C14 to C12 is 10^-12 (1:1,000,000,000,000) give or take. Since the amount of C14 is reduced by half every 5700 years it doesn’t take long for the amount of C14 in a sample to drop to a level that is barely measurable. The tools invented to make these sorts of precise measurements are impressive.

But does the method work?

As is so often the case when it comes to questions of science, those of us who are not experts in the field must try to determine whether or not to trust the science, or not, when confronted with brilliant deductions and inscrutable mathematical equations. For most of us, the only way to assess the veracity of the science is by the quality of its results. Unfortunately, as G. K. Chesterton lamented, the science of the past is not often subject to these kinds of checks.

An inventor can advance step by step in the construction of an airplane even if he is only experimenting with sticks and scraps of metal in his own backyard. But he cannot watch the Missing Link evolving in his own backyard. If he has made a mistake in his calculations, the airplane will correct it by crashing to the ground. But if he has made a mistake about the arboreal habitat of his ancestor, he cannot see his arboreal ancestor falling off the tree. He cannot keep a caveman like a cat in the backyard and watch him to see whether he does really practice cannibalism or carry off his mate on the principles of marriage by capture. He cannot keep a tribe of primitive men like a pack of hounds and notice how far they are influenced by the herd instinct… Thus while most science moves in a sort of curve, being constantly corrected by new evidence, this science flies off into space in a straight line uncorrected by anything. (“The Eternal Man”)

In the case of C14 dating, it may be possible to assess the quality of the results to some degree, at least for the Early Bronze Age, since there are other types of data with which to compare. On this basis, an early generation of scholars considered C14 dating to be “ambiguous and misleading” and not that useful for establishing a chronology of the ancient world.⁸ However, modern proponents of the method claim that C14 dating has come a long ways since those early years; labs have recalibrated and refined their methods and archaeologists have adopted complex statistical methods to analyze the results. C14 dating is now the primary and most widely accepted means of establishing an absolute chronology for the Early Bronze and earlier periods. However, I will argue that the method has tended to produce dates which are consistently too high, a problem which only grows more acute the further back in time one goes.

But what is the alternative?

There is no alternative except to use the methods that have traditionally been employed by historians and archaeologists. These include estimates of the amount of time required for debris to accumulate in an ancient mound, new forms of pottery to develop, or the span of years represented by a king list. Although lacking the technical and scientific rigor of radiocarbon dating, it is, in the words of John Maynard Keynes, “better to be roughly correct than precisely wrong.”

[Review Quiz]

Gasche, H, J. A. Armstrong, S. W. Cole, V. G. Gurzadyan. “Dating the Fall of Babylon, A Reappraisal of Second-Millennium Chronology (A Joint Ghent-Chicago-Harvard Project),” in Mesopotamian History and Envrionment, edited by L. De Meyer, H. Gasche. Series II, Memoirs IV vols. : University of Ghent and the Oriental Institute of the University of Chicago, 1998. Link
Glassner, Jean-Jacques. Mesopotamian Chronicles, edited by Benjamin R. Foster. Atlanta: Society of Biblical Literature, 2004.
Kitchen, K. A. “The Chronology of Ancient Egypt.” World Archaeology 23, no. 2 (October 1991): 201-208. Link
Kramer, S. N. The Sumerians: Their History, Culture, and Character. Chicago: University of Chicago Press, 1963. Link
Krauss, Rolf, David A. Warburton. “Conclusions,” in Ancient Egyptian Chronology, edited by Erik Hornung, Rolf Krauss, David A. Warburton. Leiden / Boston: Brill, 2006.
Thiele, Edwin. The Mysterious Numbers of the Hebrew Kings. Grand Rapids: Kregel, 1983.