Within a century of the death of Mohammad, in 632, Muslim armies had conquered almost the whole of the world where Jews lived, from Spain eastward across North Africa and the Middle East as far as the eastern frontier of Iran and beyond. Almost all the Jews in the world were now ruled by Islam. This new situation transformed Jewish existence. Their fortunes changed in legal, demographic, social, religious, political, geographical, economic, linguistic and cultural terms – all for the better.
First, things improved politically. Almost everywhere in Christendom where Jews had lived now formed part of the same political space as Babylon – Cordoba and Basra lay in the same political world. The old frontier between the vital centre in Babylonia and the Jews of the Mediterranean basin was swept away, forever.
Political change was partnered by change in the legal status of the Jewish population: although it is not always clear what happened during the Muslim conquests, one thing is certain. The result of the conquests was, by and large, to make the Jews second-class citizens.
This should not be misunderstood: to be a second-class citizen was a far better thing to be than not to be a citizen at all. For most of these Jews, second-class citizenship represented a major advance. In Visigothic Spain, for example, shortly before the Muslim conquest in 711, the Jews had seen their children removed from them and forcibly converted to Christianity and had themselves been enslaved.
In the developing Islamic societies of the classical and medieval periods, being a Jew meant belonging to a category defined under law, enjoying certain rights and protections, alongside various obligations. These rights and protections were not as extensive or as generous as those enjoyed by Muslims, and the obligations were greater but, for the first few centuries, the Muslims themselves were a minority, and the practical differences were not all that great.
Along with legal near-equality came social and economic equality. Jews were not confined to ghettos, either literally or in terms of economic activity. The societies of Islam were, in effect, open societies. In religious terms, too, Jews enjoyed virtually full freedom. They might not build many new synagogues – in theory – and they might not make too public their profession of their faith, but there was no really significant restriction on the practice of their religion. Along with internal legal autonomy, they also enjoyed formal representation, through leaders of their own, before the authorities of the state. Imperfect and often not quite as rosy as this might sound, it was at least the broad norm.
The political unity brought by the new Islamic world-empire did not last, but it created a vast Islamic world civilisation, similar to the older Christian civilisation that it replaced. Within this huge area, Jews lived and enjoyed broadly similar status and rights everywhere. They could move around, maintain contacts, and develop their identity as Jews. A great new expansion of trade from the ninth century onwards brought the Spanish Jews – like the Muslims – into touch with the Jews and the Muslims even of India.
Excerpt from article So, what did the Muslims do for the Jews? in The Jewish Chronicle by David J Wasserstein, Professor of Jewish Studies at Vanderbilt University.