7th century BC
The 7th century BC began the first day of 700 BC and ended the last day of 601 BC. The Assyrian Empire continued to dominate the Near East during this century, exercising formidable power over neighbors like Babylon and Egypt. In the last two decades of the century, the empire began to unravel as numerous enemies made alliances and waged war from all sides; the Assyrians left the world stage permanently when their capital Nineveh was destroyed in 612 BC. These events gave rise to the Neo-Babylonian Empire, which would dominate the region for much of the following century. 699 BC: Khallushu succeeds Shuttir-Nakhkhunte as king of the Elamite Empire. 697 BC: Death of King Huan of Zhou, King of the Zhou Dynasty of China. 696 BC: King Zhuang of Zhou becomes King of the Zhou Dynasty of China. 696 BC: The Cimmerians ravage Phrygia, possible migration of the Armenians. 691 BC: King Sennacherib of Assyria defeats king Humban-nimena of Elam in the Battle of Halule. 690 BC: Taharqa, a king of the Twenty-fifth Dynasty, ascends the throne of Egypt.
690s: BC—W'rn Hywt of D'mt in Ethiopia appears in the inscriptional record and mentions the king of Saba', Karib'il Watar. C. 690 BC-664 BC—Sphinx of Taharqa, from Temple T, Nubia, is made. Twenty-fifth dynasty of Egypt, it is now kept at London. 689 BC: King Sennacherib of Assyria sacks Babylon. 687 BC: Gyges becomes king of Lydia. 687 BC: Hezekiah succeeded by Manasseh as king of Judah. 682 BC: Death of King Zhuang of Zhou, King of the Zhou Dynasty of China. 681 BC: King Xi of Zhou becomes King of the Zhou Dynasty of China. 681 BC: Esarhaddon succeeds Sennacherib as king of Assyria. 677 BC: Death of King Li of Zhou, King of the Zhou Dynasty of China. 677 BC: Esarhaddon leads the Assyrian army against rebellious Arab tribes, advances as far as the Brook of Egypt. 676 BC: King Hui of Zhou becomes King of the Zhou Dynasty of China. 675 BC: Esarhaddon begins the rebuilding of Babylon. 674 BC: Esarhaddon puts down a revolt in Ashkelon supported by Taharqa, king of Egypt. In response, the Assyrians invade Egypt.
673 BC: Tullus Hostilius becomes king of Rome. 671 BC: Esarhaddon again invades Egypt, capturing Memphis as well as a number of the royal family. 669 BC: Assurbanipal succeeds his father Esarhaddon as king of Assyria. 669 BC: Argos defeats Sparta for the last time, this time using a hoplite phalanx, at the battle of Hysiae. 668 BC: Shamash-shum-ukin, son of Esarhaddon, becomes King of Babylon. 668 BC: Egypt revolts against Assyria. 668 BC: Nineveh, capital of Assyria becomes the largest city of the world, taking the lead from Thebes in Egypt. 667 BC: Byzantium founded by Megaran colonists under Byzas. 664 BC: First naval battle in Greek recorded history, between Corinth and Corcyra. 664 BC: Assurbanipal captures and sacks Thebes, Egypt. 664 BC: Psammetichus I succeeds Necho I as king of Lower Egypt. 664 BC: Taharqa appoints his nephew Tantamani as his successor of Upper Egypt. February 11, 660 BC—Traditional founding date of Japan by Emperor Jimmu. 660 BC: First known use of the Demotic script. 660 BC: Psammetichus I drives the Assyrians out of Egypt.
660 BC: Estimated date of the impact that created the Kaali crater 650s BC: The Spartan Creed by Ancient Greek poet Tyrtaeus 650s BC: Occupation begins at Maya site of Piedras Negras, Guatemala. 657 BC: Cypselus becomes the first tyrant of Corinth. 656 BC: Psammetichus extends his control over all of Egypt. End of Twenty-fifth Dynasty. 653 BC: Atta-Khumma-In-Shushinak and Khumbanigash II succeed Shilhak-In-Shushinak and Tempti-Khumma-In-Shushinak as kings of the Elamite Empire. 652 BC: Babylonia rises in revolt under Shamash-shum-ukin against the Assyrians. 652 BC: Achaemenid dynasty in Persia. 651 BC: King Xiang of Zhou becomes King of the Zhou Dynasty of China. 650 BC: The town of Abdera in Thrace is founded by colonists from Clazomenae. 650 BC: A climate change affects all the Bronze Age cultures in Europe with colder and wetter climate, tribes from the Scandinavian Nordic Bronze Age cultures are pushed downwards into the European continent. 640s BC: Assyrian king Ashurbanipal founds library, which included our earliest complete copy of the Epic of Gilgamesh.
649 BC: Indabigash succeeds Tammaritu as a king of the Elamite Empire. 649 BC: Babylonian revolt under Shamash-shum-ukin is crushed by the Assyrians. 648 BC: Pankration becomes an event at the Ancient Olympic Games. April 6, 648 BC: Earliest Greek-chronicled solar eclipse. 647 BC: King Assurbanipal of Assyria sacks Susa 642 BC: Ancus Marcius becomes king of Rome. C.641 BC: Josiah becomes king of Judah. 640 BC: Decisive victory of Assyria over Elamite Empire. 632 BC: Cylon, Athenian noble, seizes the Acropolis in a failed attempt to become king. 632 BC: In the Battle of Chengpu, the Chinese kingdom of Jin and her allies defeat the kingdom of Chu and her allies. 631 BC: Founding of Cyrene, a Greek colony in Libya. 631 BC: Sadyates becomes king of Lydia. 627 BC: Death of Assurbanipal, king of Assyria. 626 BC: Nabopolassar revolts against Assyria, founds the Neo-Babylonian Empire. 625 BC: Medes and Babylonians assert their independence from Assyria and attack Nineveh. 623 BC: Sin-shar-ishkun succeeds his brother Assur-etel-ilani as king of Assyria.
622 BC: Text of Deuteronomy found in the Temple in Jerusalem. The Hebrew prophet Ezekiel said to be born this year. 619 BC: Alyattes becomes king of Lydia. 619 BC: Death of King Xiang of Zhou, King of the Zhou Dynasty of China. 618 BC: King Qing of Zhou becomes King of the Zhou Dynasty of China. 616 BC: Lucius Tarquinius Priscus becomes
The Ethiopian calendar or Eritrean calendar is the principal calendar used in Ethiopia and serves as the liturgical year for Christians in Eritrea and Ethiopia belonging to the Eritrean Orthodox Tewahedo Church, Ethiopian Orthodox Tewahedo Church, Eastern Catholic Churches, the Coptic Orthodox Church of Alexandria, Ethiopian-Eritrean Evangelicalism. It is a solar calendar which in turn derives from the Egyptian calendar, but like the Julian calendar, it adds a leap day every four years without exception, begins the year on August 29 or August 30 in the Julian calendar. A gap of 7–8 years between the Ethiopian and Gregorian calendars results from an alternative calculation in determining the date of the Annunciation. Like the Coptic calendar, the Ethiopic calendar has 12 months of 30 days plus 5 or 6 epagomenal days, which comprise a thirteenth month; the Ethiopian months begin on the same days as those of the Coptic calendar, but their names are in Ge'ez. A 6th epagomenal day is added every 4 years, without exception, on August 29 of the Julian calendar, 6 months before the corresponding Julian leap day.
Thus the first day of the Ethiopian year, 1 Mäskäräm, for years between 1900 and 2099, is September 11. However, it falls on September 12 in years before the Gregorian leap year. Enkutatash is the word for the Ethiopian New Year in Amharic, the official language of Ethiopia, while it is called Ri'se Awde Amet in Ge'ez, the term preferred by the Ethiopian & Eritrean Orthodox Tewahedo Churchs, it occurs on September 11th in the Gregorian Calendar. The Ethiopian Calendar Year 1998 Amätä Məhrät began on the Gregorian Calendar Year on September 11th, 2005. However, the Ethiopian Years 1992 and 1996 began on the Gregorian Dates of'September 12th 1999' and'2003' respectively; this date correspondence applies for the Gregorian years 1900 to 2099. The Ethiopian leap year is every four without exception, while Gregorian centurial years are only leap years when divisible by 400; as the Gregorian year 2000 is a leap year, the current correspondence lasts two centuries instead. The start of the Ethiopian year falls on August 30th.
This date corresponds to the Old-Style Julian Calendar. This deviation between the Julian and the Gregorian Calendar will increase with the passing of the time. You can observe the real start date in the future centuries in a Gregorian to Ethiopian Date Converter. To indicate the year and followers of the Eritrean churches today use the Incarnation Era, which dates from the Annunciation or Incarnation of Jesus on March 25, AD 9, as calculated by Annianus of Alexandria c. 400. Meanwhile, Europeans adopted the calculations made by Dionysius Exiguus in AD 525 instead, which placed the Annunciation 8 years earlier than had Annianus; this causes the Ethiopian year number to be 8 years less than the Gregorian year number from January 1 until September 10 or 11 7 years less for the remainder of the Gregorian year. In the past, a number of other eras for numbering years were widely used in Ethiopia and the Kingdom of Aksum; the most important era – once used by the Eastern Christianity, still used by the Coptic Orthodox Church of Alexandria – was the Era of Martyrs known as the Diocletian Era, or the era of Diocletian and the Martyrs, whose first year began on August 29, 284.
Respective to the Gregorian and Julian New Year's Days, 31⁄2 to 4 months the difference between the Era of Martyrs and the Anni Domini is 285 years. This is because in AD 525, Dionysius Exiguus decided to add 15 Metonic cycles to the existing 13 Metonic cycles of the Diocletian Era to obtain an entire 532 year medieval Easter cycle, whose first cycle ended with the year Era of Martyrs 247 equal to year DXXXI, it is because 532 is the product of the Metonic cycle of 19 years and the solar cycle of 28 years. Around AD 400, an Alexandrine monk called Panodoros fixed the Alexandrian Era, the date of creation, on 29 August 5493 BC. After the 6th century AD, the era was used by Ethiopian chronologists; the twelfth 532 year-cycle of this era began on 29 August AD 360, so 4×19 years after the Era of Martyrs. Bishop Anianos preferred the Annunciation style as 25 March, thus he shifted the Panodoros era by about six months, to begin on 25 March 5492 BC. In the Ethiopian calendar this was equivalent to 15 Magabit 5501 B.
C.. The Anno Mundi era remained in usage until the late 19th century; the 4 year leap-year cycle is associated with the four Evangelists: the first year after an Ethiopian leap year is named the John-year, followed by the Matthew-year, the Mark-year. The year with the 6th epagomenal day is traditionally designated as the Luke-year. There are no exceptions to the 4 year leap-year cycle, like the Julian calendar but unlike the Gregorian calendar; these dates are valid only from March 1900 to February 2100. This is because 1900 and 2100 are not leap years in the Gregorian calendar, while they are still leap year
An Olympiad is a period of four years associated with the Olympic Games of the Ancient Greeks. Although the Ancient Olympic Games were established during Archaic Greece, it was not until the Hellenistic period, beginning with Ephorus, that the Olympiad was used as a calendar epoch. Converting to the modern BC/AD dating system the first Olympiad began in the summer of 776 BC and lasted until the summer of 772 BC, when the second Olympiad would begin with the commencement of the next games. By extrapolation to the Gregorian calendar, the 3rd year of the 699th Olympiad will begin in mid-summer 2019. A modern Olympiad refers to a four-year period beginning on the opening of the Olympic Games for the summer sports; the first modern Olympiad began in 1896, the second in 1900, so on. The ancient and modern Olympiads would have synchronised had there been a year zero between the Olympiad of 4 BC and the one of 4 AD, but as the Gregorian calendar goes directly from 1 BC to 1 AD, the ancient Olympic cycle now lags the modern cycle by one year.
An ancient Olympiad was a period of four years grouped together, counting inclusively as the ancients did. Each ancient Olympic year overlapped onto two of our modern reckoning of BC or AD years, from midsummer to midsummer. Example: Olympiad 140, year 1 = 220/219 BC. Therefore, the games would have been held in July/August of 220 BC and held the next time in July/August of 216 BC, after four olympic years had been completed; the sophist Hippias was the first writer to publish a list of victors of the Olympic Games, by the time of Eratosthenes, it was agreed that the first Olympic games had happened during the summer of 776 BC. The combination of victor lists and calculations from 776 BC onwards enabled Greek historians to use the Olympiads as a way of reckoning time that did not depend on the time reckonings of one of the city-states; the first to do so was Timaeus of Tauromenium in the third century BC. Since for events of the early history of the games the reckoning was used in retrospect, some of the dates given by historian for events before the 5th century BC are unreliable.
In the 2nd century AD, Phlegon of Tralles summarised the events of each Olympiad in a book called Olympiads, an extract from this has been preserved by the Byzantine writer Photius. Christian chroniclers continued to use this Greek system of dating as a way of synchronising biblical events with Greek and Roman history. In the 3rd century AD, Sextus Julius Africanus compiled a list of Olympic victors up to 217 BC, this list has been preserved in the Chronicle of Eusebius. Early historians sometimes used the names of Olympic victors as a method of dating events to a specific year. For instance, Thucydides says in his account of the year 428 BC: "It was the Olympiad in which the Rhodian Dorieus gained his second victory". Dionysius of Halicarnassus dates the foundation of Rome to the first year of the seventh Olympiad, 752/1 BC. Since Rome was founded on April 21, in the last half of the ancient Olympic year, it would be 751 BC specifically. In Book 1 chapter 75 Dionysius states: "... Romulus, the first ruler of the city, began his reign in the first year of the seventh Olympiad, when Charops at Athens was in the first year of his ten-year term as archon."
Diodorus Siculus dates the Persian invasion of Greece to 480 BC: "Calliades was archon in Athens, the Romans made Spurius Cassius and Proculus Verginius Tricostus consuls, the Eleians celebrated the Seventy-fifth Olympiad, that in which Astylus of Syracuse won the stadion. It was in this year that king Xerxes made his campaign against Greece." Jerome, in his Latin translation of the Chronicle of Eusebius, dates the birth of Jesus Christ to year 3 of Olympiad 194, the 42nd year of the reign of the emperor Augustus, which equates to the year 2 BC. An Olympiad started with the holding of the games, which occurred on the first or second full moon after the summer solstice, in what we call July or August; the games were therefore a new years festival. In 776 BC this occurred on either July 23 or August 21.. Though the games were held without interruption, on more than one occasion they were held by others than the Eleians; the Eleians declared such games Anolympiads, but it is assumed the winners were recorded.
During the 3rd century AD, records of the games are so scanty that historians are not certain whether after 261 they were still held every four years. During the early years of the Olympiad, any physical benefit deriving from a sport was banned; some winners were recorded though, until the last Olympiad of 393AD. In 394, Roman Emperor Theodosius. Though it would have been possible to continue the reckoning by just counting four-year periods, by the middle of the 5th century AD reckoning by Olympiads had become disused; the modern Olympiad is a period of four years, beginning at the opening of the Olympic Summer Games and ending at the opening of the next. The Olympiads are numbered consecutively from the first Games of the Olympiad celebrated in Athens in 1896; the XXXI Olympiad began on August 5, 2016 and will end on July 24, 2020. The Summer Olympics are more referred to as the Games of the Olympiad; the first poster to announce the games using this term was the one for the 1932 Summer Olympics, in Los Angeles, using the phrase: Call to the games of the Xth Olympiad Note, that the official numbering of the Winter Olympics does
Twenty-sixth Dynasty of Egypt
The Twenty-sixth Dynasty of Egypt was the last native dynasty to rule Egypt before the Persian conquest in 525 BC. The dynasty's reign is called the Saite Period after the city of Sais, where its pharaohs had their capital, marks the beginning of the Late Period of ancient Egypt; this dynasty traced its origins to the Twenty-fourth Dynasty. Psamtik I was a descendant of Bakenranef, following the Neo-Assyrian Empire's invasions during the reigns of Taharqa and Tantamani, he was recognized as sole king over all of Egypt. While the Neo-Assyrian Empire was preoccupied with revolts and civil war over control of the throne, Psamtik threw off his ties to the Assyrians circa 655 BC, formed alliances with King Gyges of Lydia, recruited mercenaries from Caria and ancient Greece to resist Assyrian attacks. With the sack of Nineveh in 612 BC and the fall of the Assyrian Empire, both Psamtik and his successors attempted to reassert Egyptian power in the Near East, but were driven back by the Neo-Babylonian Empire under Nebuchadnezzar II.
With the help of Greek mercenaries, Apries was able to hold back Babylonian attempts to conquer Egypt, only for the Persians to do so. Their king, Cambyses II, captured and executed Psamtik III; the 26th Dynasty may be related to the 24th Dynasty. Manetho begins the dynasty with: Ammeris the Nubian, 12 years Stephinates, 7 years Nechepsos, 6 years Necho, 8 years; when the Nubian King Shabaka defeated Bakenranef, son of Tefnakht, he installed a Nubian commander as governor at Sais. This may be the man named Ammeris. Stephinates may be a descendant of Bakenrenef, he is sometimes referred to as Tefnakht II in the literature. Nechepsos has been identified with a local king named Nekauba. Manetho's Necho is King Necho I. Necho was killed during a conflict with the Nubian king Tantamani. Psamtik I fled to Nineveh – capital of the Neo-Assyrian Empire – and returned to Egypt when Ashurbanipal defeated Tantamani and drove him back south. Scholars now start the 26th Dynasty with the reign of Psamtik I. Sextus Julius Africanus states in his accurate version of Manetho's Epitome that the dynasty numbered 9 pharaohs, beginning with a "Stephinates" and ending with Psamtik III.
Africanus notes that Psamtik I and Necho I ruled for 54 and 8 years respectively. History of ancient Egypt Twenty-sixth Dynasty of Egypt family tree Late Period of ancient Egypt Saite Oracle Papyrus Aidan Dodson, Dyan Hilton; the Complete Royal Families of Ancient Egypt. The American University in Cairo Press, London, 2004. Kenneth Kitchen, The Third Intermediate Period in Egypt, 1100–650 B. C. Aris & Phillips. 1986 ISBN 978-0-85668-298-8. Karl Jansen-Winkeln, Bild und Charakter der ägyptischen 26. Dynastie, Altorientalische Forschungen, 28, 165–182
The Byzantine calendar called "Creation Era of Constantinople" or "Era of the World", was the calendar used by the Eastern Orthodox Church from c. 691 to 1728 in the Ecumenical Patriarchate. It was the official calendar of the Byzantine Empire from 988 to 1453, of Kievan Rus' and Russia from c. 988 to 1700. Since "Byzantine" is a historiographical term, the original name uses the noun "Roman" as it was how the Eastern Roman Empire continued calling itself; the calendar was based on the Julian calendar, except that the year started on 1 September and the year number used an Anno Mundi epoch derived from the Septuagint version of the Bible. It placed the date of creation at 5509 years before the Incarnation, was characterized by a certain tendency, a tradition among Jews and early Christians to number the years from the calculated foundation of the world, its Year One, marking the supposed date of creation, was September 1, 5509 BC, to August 31, 5508 BC. It is not known when; the first appearance of the term is in the treatise of a certain "monk and priest", who mentions all the main variants of the "World Era" in his work.
Georgios argues that the main advantage of the World era is the common starting point of the astronomical lunar and solar cycles, of the cycle of indictions, the usual dating system in Byzantium since the 6th century. He already regards it as the most convenient for the Easter computus. Complex calculations of the 19-year lunar and 28-year solar cycles within this world era allowed scholars to discover the cosmic significance of certain historical dates, such as the birth or the crucifixion of Jesus; this date underwent minor revisions before being finalized in the mid-7th century, although its precursors were developed c. AD 412. By the second half of the 7th century, the Creation Era was known in Western Europe, at least in Great Britain. By the late 10th century around AD 988, when the era appears in use on official government records, a unified system was recognized across the Eastern Roman world; the era was calculated as starting on September 1, Jesus was thought to have been born in the year 5509 since the creation of the world.
Historical time was thus calculated from the creation, not from Christ's birth, as in the west after the Anno Domini system was adopted between 6th and 9th centuries. The Eastern Church avoided the use of the Anno Domini system of Dionysius Exiguus, since the date of Christ's birth was debated in Constantinople as late as the 14th century. Otherwise the Byzantine calendar was identical to the Julian Calendar except that: the names of the months were transcribed from Latin into Greek; the leap day of the Byzantine calendar was obtained in an identical manner to the bissextile day of the original Roman version of the Julian calendar, by doubling the sixth day before the calends of March, i.e. by doubling 24 February. The Byzantine World Era was replaced in the Orthodox Church by the Christian Era, utilized by Patriarch Theophanes I Karykes in 1597, afterwards by Patriarch Cyril Lucaris in 1626, formally established by the Church in 1728. Meanwhile, as Russia received Orthodox Christianity from Byzantium, she inherited the Orthodox Calendar based on the Byzantine Era.
After the collapse of the Byzantine Empire in 1453, the era continued to be used by Russia, which witnessed millennialist movements in Moscow in AD 1492. It was only in AD 1700 that the Byzantine World Era in Russia was changed to the Julian Calendar by Peter the Great, it still forms the basis of traditional Orthodox calendars up to today. September AD 2000 began the year 7509 AM; the earliest extant Christian writings on the age of the world according to the Biblical chronology are by Theophilus, the sixth bishop of Antioch from the Apostles, in his apologetic work To Autolycus, by Julius Africanus in his Five Books of Chronology. Both of these early Christian writers, following the Septuagint version of the Old Testament, determined the age of the world to have been about 5,530 years at the birth of Christ. Ben Zion Wacholder points out that the writings of the Church Fathers on this subject are of vital significance, in that through the Christian chronographers a window to the earlier Hellenistic biblical chronographers is preserved: An immense intellectual effort was expended during the Hellenistic period by both Jews and pagans to date creation, the flood, building of the Temple...
In the course of their studies, men such as Tatian of Antioch, Clement of Alexandria, Hippolytus of Rome
This article concerns the period 599 BC – 590 BC. 599 BC—Vardhamana Mahavira, last Tirthankara of Jainism, is born. 598 BC—Jeconiah succeeds Jehoiakim as King of Judah. March 16, 597 BC—Babylonians capture Jerusalem following a siege, replace Jeconiah with Zedekiah as king and send many Jews into Babylonian captivity. 595 BC—Psamtik II succeeds Necho II as king of Egypt. 595 BC—in Zhou Dynasty China, the State of Jin is defeated by the State of Chu in the Battle of Bi. 594 BC—The leaders of Athens, facing an economic crisis and popular discontent, appoint the poet–statesman Solon to institute democratic reforms and revive the city's constitution, extending citizenship to males of many classes. 593 BC—Exile of Sappho and Alcaeus of Mytilene in Sicily. 592 BC—Early history of Sudan: An Egyptian army sacks Napata, compelling the Cushite court to move to a more secure location at Meroe near the sixth cataract of the Nile. Mahavira, the 24th Tirthankara of Jainism
The majority of Egyptologists agree on the outline and many details of the chronology of Ancient Egypt. This scholarly consensus is the so-called Conventional Egyptian chronology, which places the beginning of the Old Kingdom in the 27th century BC, the beginning of the Middle Kingdom in the 21st century BC and the beginning of the New Kingdom in the mid-16th century BC. Despite this consensus, disagreements remain within the scholarly community, resulting in variant chronologies diverging by about 300 years for the Early Dynastic Period, up to 30 years in the New Kingdom, a few years in the Late Period. In addition, there are a number of "alternative chronologies" outside scholarly consensus, such as the "New Chronology" proposed in the 1990s, which lowers New Kingdom dates by as much as 350 years, or the "Glasgow Chronology", which lowers New Kingdom dates by as much as 500 years. Scholarly consensus on the general outline of the conventional chronology current in Egyptology has not fluctuated much over the last 100 years.
For the Old Kingdom, consensus fluctuates by as much as a few centuries, but for the Middle and New Kingdoms, it has been stable to within a few decades. This is illustrated by comparing the chronology as given by two Egyptologists, the first writing in 1906, the second in 2000; the disparities between the two sets of dates result from additional discoveries and refined understanding of the still incomplete source evidence. For example, Breasted adds a ruler in the Twentieth dynasty that further research showed did not exist. Following Manetho, Breasted believed all the dynasties were sequential, whereas it is now known that several existed at the same time; these revisions have resulted in a lowering of the conventional chronology by up to 400 years at the beginning of Dynasty I. Forming the backbone of Egyptian chronology are the regnal years as recorded in Ancient Egyptian king lists. Surviving king lists are either comprehensive but have significant gaps in their text, or are textually complete but fail to provide a complete list of rulers for a short period of Egyptian history.
The situation is further complicated by occasional conflicting information on the same regnal period from different versions of the same text. Regnal periods have to be pieced together from inscriptions, which will give a date in the form of the regnal year of the ruling pharaoh, yet this only provides a minimum length of that reign and may or may not include any coregencies with a predecessor or successor. In addition, some Egyptian dynasties overlapped, with different pharaohs ruling in different regions at the same time, rather than serially. Not knowing whether monarchies were simultaneous or sequential results in differing chronological interpretations. Where the total number of regnal years for a given ruler is not known, Egyptologists have identified two indicators to deduce that total number: for the Old Kingdom, the number of cattle censuses. A number of Old Kingdom inscriptions allude to a periodic census of cattle, which experts at first believed took place every second year. However, further research has shown that these censuses were sometimes taken in consecutive years, or after two or more years had passed.
The Sed festival was celebrated on the thirtieth anniversary of a pharaoh's ascension, thus rulers who recorded celebrating one could be assumed to have ruled at least 30 years. However, once again, this may not have been standard practice in all cases. In the early days of Egyptology, the compilation of regnal periods was hampered by a profound biblical bias on the part of Egyptologists; this was most pervasive before the mid 19th century, when Manetho's figures were recognized as conflicting with biblical chronology, based on Old Testament references to Egypt. In the 20th century, such biblical bias has been confined to alternative chronologies outside the scholarly mainstream. A useful way to work around these gaps in knowledge is to find chronological synchronisms, which can lead to a precise date. Over the past decades, a number of these have been found, although they are of varying degrees of usefulness and reliability. Seriation, i.e. archeological sequences. This does not fix a person or event to a specific year, but establishing a sequence of events can provide indirect evidence to provide or support a precise date.
For example, some inscribed stone vessels of the rulers of the first two dynasties were collected and deposited in storage galleries beneath and sealed off when the Step Pyramid of Djoser, a Pharaoh of the Third Dynasty, was built. Another example are blocks from the Old Kingdom bearing the names of several kings, which were reused in the construction of Middle Kingdom pyramid-temples at Lisht in the structures of Amenemhat I; the third pylon at Karnak, built by Amenhotep III contained as "fill" material from the kiosk of Sesostris I, along with various stelae of the Second Intermediate Period and the Eighteenth Dynasty of the New Kingdom. Synchronisms with other chronologies, the most important of these being with the Assyrian and Babylonian chronologies, but synchronisms with the Hittites, ancient Palestine, in the final period with ancient Greece, are used; the earliest such synchronism is in the 18th century