Jits van Straten - the controversy unraveled

August 2014.

Last week i read a very interesting book by Jits van Straten: The Origin of Ashkenazi Jewry: The Controversy Unraveled. New York: Walter de Gruyter, 2011. xii + 234 pp. $120.00 (cloth), ISBN 978-3-11-023605-7. Actually i read the Dutch version, which appeared two years earlier and had a better price.

I also read a review by Paul Wexler on the book.

The "Controversy" in the title was raised by Renan in 1883: The Jewish population in Eastern Europe is too large to accept the common thought that the Ashkenazim went from Germany to Eastern Europe. Probably they descend from the South-Russian Khazaria, which was ruled by a Royal family and upper class that chose Jewish as a religion. They are not genetic descendants from Judea. If they would descend from German Jews who arrived at the end of the middle ages, the required population growth would be unrealistic high.

The book has five parts:

• Historic facts and discussions on where and when the Jews were in Europe and Caucasus regions.
• A model to describe the population growth between 1500 and 1900
• A discussion on the origin of Jiddisch.
• A discussion on the DNA knowledge at the time the book was written.
• An analysis by Jits van Straten where he concludes that the East-European Jews originate from Southern Russia.

Jils van Straten does a good job and gives a good overview on the subjects of the book, in particular the historic facts and discussions. I was disappointed on the DNA-chapter. Apart from the incorrect statements, the knowledge has changed dramatically. I considered his model on population growth interesting, but only interesting on the period 1500-1900. The model and DNA-knowledge as discussed on this website has the opportunity to compare model with observations in the years 0-1900 CE.

The title of the book suggests a clear final conclusion. This is not present in the book.

Knowledge

• The Jews were in the Eastern European area before the 11th century. They probably controlled the merchant routes along the line Prague-Krakau-Przemysl-Kiev. A control of the merchant routes is similar as the routes the were controlled by the Jewish Radhanites. Van Straten also argues that being Jewish was advantage for a merchant in a world that was divided in Christian and Moslem powers. It made it possible to trade between both powers.
• Jiddisch is by origin a German (Bavarian) language that used as a teaching language in Prague by Rabbi's. They spoke the German language with a natural influence by the local (Czech) language in Prague and the Hebrew words in the Talmud. The knowledge of the Talmud was high in Prague (and Germany), and low in Eastern Europe in the 12th-15th century. The students from the Eastern Jewish areas (first Ukrainian and later more northern area of Poland-Lithuania) learned the language and it became the first language of the Jews in Eastern Europe.
  Van Straten argues that the Jewish people in Eastern Europe spoke the local language until Jiddisch was used as a first language.

Consistent results with this website

• The population growth of Congres-Poland was a factor of 2.9 for the overall population and 3.5 for Jews between 1800-1900. He uses this as a basic population growth ratio of the Jewish population. In this period it gives a population growth per year of 1.011 for the overall population and 1.013 per year for the Jewish population. He assumes this ratio 1.013/1.011 is constant.
  • The best model (model 4) described on this website gives a population growth of the Jewish population in the period until 1600 of 1.007 per year. Both models are sufficient to describe a scenario that fits the historic information: no strong political tension is present due to fast changing population ratios (population explosion of the Jewish population).
• The population explosion of Ashkenazim in Eastern Europe probably did not take place as an explosion. It was a gradual growth that started long before the 16th century.
  • This conclusion was also drawn on this website on tmrca calculations on the STR-variability of Y-DNA Ashkenazi branches.

Inconsistent results with this website

• The Jews mixed strongly with the the Y-DNA groups people local in the Eastern European area.
  • This is not supported by the Y-DNA data. The amount of Ashkenazi Y-DNA branches is small. In case Jews mixed strongly (e.g. one percent in each generation), the number of Eastern European Y-DNA branches is expected higher. We would expect at least 10 percent in 300 years of mixture. The distribution of the Ashkenazi branches does not show such high values of mixture. Only two branches suggest a likely origin in Eastern-Europe: I1-Z140 and R1a-L1029. They represent less than one percent of the Ashkenazi Jews.
• The Jews were probably in Eastern Europe in the year 0 CE.
  • There is no reason to conclude this. A simple model (model 4 in the Simulations section of this website) uses an influx of 20 groups of 20 people between the years 700 and 1500 are sufficient to describe the observed data.
• The DNA of the Eastern European Jewish is different from Jews from the Germanic areas.
  • I made a diagram below to see if this is plausible. I ordered the Ashkenazim branches by size, which roughly represent the time order they arrived in Germanic countries and Eastern Europe. Number one is the largest group (J2a-L556), etc. The origin that was reported is grouped in the groups: Eastern Europe in orange, Germanic countries (Germany, Austria, Czech, Netherlands) in blue. It appears that the percentage of blue does not change significantly as function of branch size (which is approximately arrival time). We have to conclude that mixture between Jewish groups in Germanic countries and Eastern European countries is present. There is no reason to conclude they developed independently.