Answer:
The whole structure of European society changed in the 12th and 13th centuries, and there was a time when this change was mainly attributed to the Crusades. Now, however, historians tend to view the Crusades as only one, albeit important, factor in the development of Europe. Probably the disappearance of old families and the emergence of new ones can be traced in part to the Crusades, but summaries must be made with caution.
