Answer: The original intent of credit union law in the U.S. did not limit fields of membership. Community charters were rather common. Due to the growing number of credit unions, identifying a specific membership group made it easier to distinguish membership areas, thereby eliminating confusion of a credit union’s intended area.
Credit unions began expanding their fields of membership to serve groups who didn’t have the means or numbers to establish their own credit unions. Diversification of the membership also provides additional safety during economic downturns. If one group is experiencing hard times, the other groups can help sustain the credit union.