Unlike the Egyptians, the Assyrians kept careful records of astronomical events, recording the date and time of every eclipse of the sun and moon. This means that we can fix these events to the very day and often to the hour.
In addition the Assyrians kept lists of the names of men who were appointed as limus or governors for the term of a single year, rather like Roman consuls. These lists, known as Limu Lists, enable us to be absolutely precise about Assyrian history.
It is possible to link the chronology of Israel to that of Assyria thanks to the rather quirky way in which the Jews kept their historical records. It all comes down to the fact that people back then did not have a common era like our AD and BC. They knew that years went round in cycles - summer, winter, spring time, harvest - and they had a point which they recognised as the new year - for some it was the spring, for others the autumn - but the only way they had of identifying a particular year was in terms of the king's reign.
People dated events in the third year or the fifteenth year or whatever of king so-and-so. For example, you might have a receipt dated in the third year of King Nabonidus or a marriage contract dated to the fifteenth year of Cyrus.
This system worked, but it was hard going. If we think in modern terms, I was born in the 12th year of King Edward VIII, my wife was born in his 11th year, but my firstborn son was born in the 20th year of Queen Elizabeth. If you want to work out how old I am, you have to know how many years King Edward VIII reigned and whether there were any monarchs in between him and the present queen.
As you can see, the system is awkward and inconvenient, but it works after a fashion. However there was one problem that the ancients never really solved. You see, if a king dies on December 31 and his son comes to the throne on January 1, everything is clear and simple. December 31 is the final year of the old king, January 1 is the first year of the new king.
Unfortunately royalty is rarely so considerate: they usually die at some untidy time like February 23 or August 12 - so what happens then? It's obvious that the time up until the old king's death is part of his final year, but what about the rest of the year?
Well, some cultures decided that the rest of the year was the new king's first year - and if the old king died on December 15, you had the ridiculous situation that the new king's first year was 16 days long! I guess the people back then understood the situation and coped with it, but it leads to all sorts of complications for modern historians. We just can't win!
Imagine a king - let's call him King One - who dies on November 30. His son, King Two, comes to the throne on December 1 and his "first year" is all of one month long. However King Two catches whatever it was that was going round - some horrible plague or other - and he dies on January 31, so his second year was also one month long. That means that his total reign was two months, but in the records of the kingdom and in our history books he will be down for two years!
Other cultures, however, tackled the problem in a different way. Instead of calling the first few months of the new king's reign his "first year", they called it his "accession year", the year he came to the throne. This kept the count of years more accurate, but it did mean that a king might reign for 23 months yet only be credited with a single year on the throne - which again can lead to problems for the historians.
Back in the first lesson I listed the countries that had written records - Egypt, Mesopotamia and the Hittites. I left one out: Palestine. Israel kept written records that have come down to us as the Bible. In fact, the Bible contains two accounts of the history of this area: one is known as the Books of Kings and the other is the Books of Chronicles. Kings appears to have been written based on the records of the northern kingdom of Israel, Chronicles is based on the records of the southern kingdom, Judah.
The interesting thing is that the people who kept these records dated events in terms of their king's reign - as you would expect - but they also frequently dated things in terms of the reign of the next door king, so the scribes of Judah might give you the year of the reign of the king of Israel and the scribes of Israel do the same for the king of Judah. The most common time when this happened was when a new king came to the throne. For example, here in 1 Kings 22:41 we have the account of the beginning of the reign of King Jehoshaphat.
Jehoshaphat the son of Asa became king of Judah in the fourth year of Ahab king of Israel. Jehoshaphat was thirty-five years old when he became king and he reigned in Jerusalem for twenty-five years.
And seeing as we have mentioned Jehoshaphat's father Asa and king Ahab, here is the account of the start of Ahab's reign in 1 Kings 16:29:
In the thirty-eighth year of Asa king of Judah, Ahab son of Omri became king of Israel and he reigned in Samaria over Israel for twenty-two years.
This sort of cross-referencing is called a synchronism.
Unfortunately, if you simply add all the lengths of reign together for the two kingdoms, you get wildly different chronologies and if you try to work it out using the synchronisms you end up in a fearful muddle. Believe me. I've tried it!
Back in 1951 a man called Edwin R. Thiele, a professor at Emmanuel College in America, tried to work it out. He was the first, as far as I know, to recognise the problem I explained earlier of accession year reckoning or non-accession year reckoning. He noted that after the division of Solomon's kingdom between Jeroboam and Rehoboam, if you worked things out using the synchronisms in the text, at every new reign the reckoning of the northern kingdom gained a year compared with the southern kingdom - and this gave him the vital clue to what was going on.
But he noted something else very important for our story: he noted that using the method he had worked out, there were exactly twelve years between the last year of King Ahab's reign and the first year of King Jehu's reign. The interesting thing is that in the British Museum there is a stele, the Kirkuk Stele, which tells how the Assyrian King Shalmaneser III led an unsuccessful invasion into Syria in 853 BC. He notes the names of the kings who opposed him and prominent in the list is King Ahab, who provided the second-largest contingent of chariots.
On the Black Obelisk of Shalmaneser III we have a picture of King Jehu paying tribute to Shalmaneser in 841 BC - and because the Assyrian chronology is so accurate and precise, we know that these two events were exactly twelve years apart. In other words, Thiele discovered that Ahab must have taken part in the Battle of Qarqar in his final year and Jehu must have paid tribute to Shalmaneser in his first year.
That means that thanks to these two monuments, we are able to fix the reigns of these two kings in history and we can say that Ahab's final year was 853 BC and Jehu's first year was 841 BC.
But more than that: because of this business of the Israelite records gaining one year for each new king, we can have confidence that the records are accurate right back to the end of Solomon's reign and, as the Bible tells us how long Solomon ruled for, we can fix the start of his reign at 971 BC.