[Patrick_k]

"The Jews were military allies of the Muslims in some areas"

I really doubt this. The 'Israelites', as they were called, did not constitute a compact political entity in any part of the muslim world of the 11th century. But killing the whole population of a city after its defeat was very common. As there was no way to identify friend from foe, especially when they both spoke a same completely different unknown language.

But the fact that Jews were then living in 'relative' peace within moslem communities in the moslem world is very well known to the scholars. Look at

http://en.wikipedia.org/wiki/Maimonides

You might as well have a small idea of what was the intellectual mood in the 12th century.

[Varda]

Yes, the fact Jews were then living in 'relative' peace within moslem communities" is not surprising.

" According to surviving records, Jews helped the Arabs in many places. From Syria to Spain, they opened city gates to the besieging armies; and in Spain, they often garrisoned the captured cities to enable the Muslims to sweep on to further conquests....
Jews, accustomed to adversity, found their change of masters an improvement. They survived the hardship brought about by the conquest and were eventually able to participate in the creation of the new Arabic civilisation that followed."
(The Jews of Arabia, http://www.dangoor.com/71page33.html)