whether Jesus was the true Messiah. By the beginning of the fourth century, Christianity had evolved with customs, rituals and laws far different from Judaism.
Palestine was conquered by the Arabs in the 7th century. Many Jews served in the Arab armies which conquered the Iberian peninsula, and settled in Spain. For centuries, Jews flourished in Spain and North Africa, and recorded achievements in science, medicine, music, philosophy and culture.
Jewish life in the Middle Ages was for the most part a story of social and economic isolation, persecution and massacres. Jews were isolated both physically and socially from the fabric of life in the Middle Ages and the period following the Middle Ages. Yet they filled an important niche. Christianity outlawed usury, the lending of money. Jews were permitted to fill this vacuum by acting as moneylenders and financiers.
Ghettos
At first, Jews in the diaspora segregated voluntarily. This was partly for self-protection, but it was perhaps more the result of the requirements of the Jewish religion: to be close to a synagogue and other religious institutions. The concept of segregating Jews involuntarily behind walls was developed in ancient times, but it was not actually implemented as a policy until 1462 in Frankfurt, Germany. The idea caught on in the rest of Europe and became the norm in the 16th century. Unlike its modern 20th century counterpart, the ghetto of 16th century Europe permitted Jews to leave during the day and do their business. While the ghettos permitted Jews to live peacefully, conditions were often crowded and inadequate. However, the isolation of Jews in ghettos had the effect of eliminating assimilation with the host communities, and