What I initially liked about the book is that in articles Sand emphasised the diversity of early Jews, and that they were happy to convert, in fact did so enthusiastically.
It's a point I've made before:
In the early first century AD Judaism was a proselytizing religion, and attracted a large number of followers. The main reason it did not close the deal with more converts was that the rabbis were intransigent about one issue: circumcision. Men were reluctant to give up a piece of themselves.
Early Christianity under Paul was more flexible. At the Council of Jerusalem (ca. AD 50), the followers of Jesus re-stated that most of the laws of Moses were to be kept - such as the requirement to keep kosher. There were two major departures from Jewish law, which would in effect change the course of history.
The first was waving the circumcision requirement, which immediately let to a flood of converts.
King Herod and the Herodian Dynasty inter-married and encouraged conversions - more on that here and here. Helena of Adiabene is a famous convert of the time whose tomb in Jerusalem is extant (for information on her sarcophagus see here).
In fact it's very difficult to tell in many of the early Roman sources whether they are writing about Christians or Jews converting people, but we do know that both were enthusiastic.
Flavia Domitilla is a good example. A member of the Imperial family, she was accused of "αθεοτση ... drifting into the Jewish ways" (Epitome of Cassius Dio, 67.4). But this atheism or monotheism was later interpreted as Christianity so to Christians she's a Christian saint with catacombs named after her. Yet according to the Talmud Rabbi Akiva be Joseph converted her to Judaism ... and she has a nice long entry in the Jewish Encyclopedia! So Eusebius later says Domatilla became a Christian, but Jewish sources make her and her husband the Consul Titus Flavius Clemens Jews ...
I also liked Sand's questioning of the Diaspora. Yes, a lot of Jews were transported to Babylon - many returned to the Holy Land, some stayed there, whilst others moved further east. But we don't know of large scale displacements of entire populations by the Romans during the Imperial period, such as the one they are assigned after the Bar Kokhba Revolt in the 130s AD. It's become a key tenet of Jewish history, but would not be normal for Roman history. In earlier periods entire populations were killed or enslaved after wars, but not normally during the Imperial period - I can't cite an ancient source to support this, because sources tend not to write about things that didn't happen (although conversely they do sometimes fail to write about things that did, for example Hunnic head binding and their strange skulls).
Jews had been moving around the Mediterranean and the Middle East, both of their own volition and by force, for centuries. There was an interesting study a few years ago that claimed "Ancient maritime traders of the Mediterranean may have left behind a large genetic footprint in the region, where 1 in 17 men still harbors Phoenician DNA" (quote from a National Geographic summary) The full study, Identifying Genetic Traces of Historical Expansions: Phoenician Footprints in the Mediterranean, can be found here. I'm not going to even pretend to understand genetic studies in anything more than a superficial way, so I can't argue the science. What I can point out is that their 'Phoenecian' original samples come from an area now better known for it's Jewish population, and which in Antiquity had a diverse population. And the modern descendants of these 'Phoenecians' were found by the researchers all around the Med - whilst Punic colonies and towns tended to be in North Africa (Carthage), in Spain, and in Sicily and Southern Italy (Motya). To me it would make more sense if they had said that 1 in 17 men had DNA from the area which is now Israel, and it would also make more sense if they were descended from Jews that settled around the Mediterranean and inter-married, which is well attested throughout history.
So far I have no problem with Sand, and I've even cited a DNA study that can easily be argued to support him.
Where it all goes wrong is with another DNA study and more conversions - the Khazars.
In 1976 Arthur Koestler published The Thirteenth Tribe, which theorised that: the Khazars had converted en masse to Judaism in the middle Byzantine period, that their kingdom had been wiped off the face of the earth a couple of centuries later, and that although they had 'vanished' from history, they had in fact migrated via Russian into Eastern Europe, and that their descendants were the Ashkenazim. As a theory it was interesting, but it was taken up by many anti-Semitic extremists to argue that this meant that Jews did not have a right to Israel, and it became problematic.
It also excluded some facts. A letter from the Cairo Genizah and now in Cambridge - the "Schechter Letter" - was written around AD 930 and discusses the conversion of the Khazars to Judaism. Rather than being some strange unexplained mass conversion of the population, the letter and other surviving documents of the period suggest that it was a 'return' to practising Judaism by the local aristocracy, many of who were descended from Persian Jews that had migrated to the region centuries before. There were also conversions by some descendants of the native population, but the Khazars were extremely tolerant of other religions and the conversions to Judaism do not seem to have been forced or widespread beyond the ruling class. The Jewish Khazars were not wiped out by the Rus invaders, simply removed from power and continued to exist in the regions for many centuries.
Since then Ashkenazim descent solely from the Khazars has been conclusively disproven by a number of studies, which show that they are directly related to the Jews which inhabited Israel (the main study is here: Y chromosome evidence for a founder effect in Ashkenazi Jews). There have been a lot of studies of various Jewish groups' DNA, as there has been of other groups, and they have proven interesting.
But it's with the Khazar / Ashkenazi / Thirteenth Tribe theory that Sand lost me. If he's so out of date in his research, and so wrong when dealing with periods I know a bit about, I worry about his theories and research in areas I don't know about. I worry about people without a solid background in history quoting a book which has sold so many copies, and abusing the theories.
One area that seems to worry people, presumably because they fear that it will be abused to claim Jews have no right to Israel, is Sand's point that many Jews in what is now Israel stayed and converted. They did. First they converted to paganism under the Romans, so as to be able to achieve office and rise in society, then they converted to Christianity after Constantine, and later to Islam after Mohammed. I'm writing a book on woman in the ancient world that led armies, and the last one I'm covering is Aisha, the widow of Mohammed, who fought his son-in-law Ali at the Battle of the Camel. Although I have some background in the period, I've been researching early Islam, and it amazes me how many Jews there were in Arabia, particularly in Medina, many of which converted to Islam. Many Palestinians were probably Jewish if one goes back far enough. I assume that it doesn't make me an anti-Semite to acknowledge this historical fact.
The conversion of the rulers of Himyar in the Yemen to Judaism remains and enigma, but must, I suspect, have something to do with the strong historical ties between the Yeman and Ethiopia, or the Jewish tribes in Arabia. The conversion of their king took place either in the fourth or early fifth century AD. At the time, and right into the lifetime of Mohammed, there were Jewish tribes in Arabia, who had migrated from Israel over the centuries. The Beta Israel ('Falasha') have now migrated from Ethiopia to Israel, but attest to a long tradition of Jews in Israel.
One theory is that they arrived in Ethiopia with trade, another that they descended through Egypt, which had the only two Temples outside Jerusalem (see here and here; the difference is that sacrifices were made in a Temple, but not in a synagogue).
Yes, people converted and inter-married (two such people produced me), and Jewish history is not as simple as some people would like it to sound, but history rarely is. Non-Jews converted to Judaism, Jews converted to other religions, but we're mostly descended from the people that once inhabited the land that is now Israel. I found Sand's The Invention of the Jewish People to be a deeply flawed book. It is however worth reading for those interested in history, even if you have to take a lot of what he writes with a (large) grain of salt, because it is thought-provoking.
The Invention of the Jewish People - Amazon.co.uk
The Invention of the Jewish People - Amazon.com