New Social Patterns

Even though the crusades were disastrous, they set the background for the development of new patterns of social relationship in Europe:

Crusades provided new sources of wealth as Europeans established trading presence in the Mediterranean. 

Crusades involved forging of new alliances between merchants and rulers.  Result of relatively impoverished ruling classes and relatively affluent merchants but proves a highly dynamic (and far from inevitable) combination.

1100-1500