Jewish Social Life and Customs
A Jew is any person whose mother was a Jew or any person who has gone through the formal process of conversion to Judaism. Being a Jew is not a matter of belief. According to Jewish law, even if a person believes everything that Orthodox Jews believe and observes every law and custom of Judaism, he or she is not considered a Jew unless he or she meets the requirement of a Jewish mother or formal conversion. A person born to a Jewish mother who is atheist and does not practice the Jewish religion is still a Jew. In this sense, being Jewish is more like a nationality than a religion.
Effective family research requires some understanding of the society your ancestor lived in. Learning about everyday life, religious practices, customs, and traditions will help you appreciate your ancestor and the time he or she lived in. This information is particularly helpful if you choose to write a history of your family.
Research procedures may be affected by local customs and traditions, including marriage customs. Jews sometimes married close relatives, marriage among first cousins being legal among the Jews. Such marriage unions were more common among Sephardic Jews than among the Ashkenazic. Until the 20th century Jews commonly married early: young men between 15 and 18 and young women between 14 and 18. Marriages were often arranged by the families, even across the ocean.
Naming customs can also affect your research. These varied between Sephardic and Ashkenazic Jews. See “Names, Personal” in these Wiki pages for specific details about naming traditions.
The Family History Library has collected a few sources which discuss a variety of subjects related to Jewish social life and customs. Check for these records in the Place Search of the FamilySearch Catalog with the topic "Social Life and Customs", or in the Subject Search under the topic "Jews". Books on this topic are also available through most Jewish publishers and bookstores.