Colonial American Naming Patterns
In the early colonies, the eldest son was generally given the same name as his father. The second son was often given the first name of one of his uncles, generally the father's oldest brother. (paternal usually, unless the father had no brothers, then a maternal uncle). The middle name was either his mother's maiden name, or grandmother's maiden name. In some cases, especially in larger familes, younger sons were given the paternal grandmothers maiden name as a given name.
Basically, as more children were born, more maiden names were used, but generally those in the direct line. Great grandmothers, great great grandmothers, etc. Children were often named after local heroes, or in the case of southern families, famous southern political personalities, such as Robert E. Lee, Francis Marion, Jackson, Jefferson Davis, etc, especially around the time of the civil war. Quite often these types of namings meant that the family naming patterns disappeared for a generation, but they generally returned in the next generation.
Women's names follow the same practices as men's names, but generally follow the maternal line. The eldest daughter is often named for her maternal grandmother. Once again maiden names are often used as middle names.
Sometimes, if the family is very large, you will only find one or two daughters with a maiden name as a middle name. Ironically, this naming pattern often makes it easy female ancestors, by taking the first name of the eldest daughter, and the middle name of the second son, you often get the grandmother.
Later, families devised their own system to ensure that their offspring inherited. ie., giving all children the same middle name, denoting the fact that all with that name could inherit, and not just the oldest son.