I would modify Barry's headings in a few details. Country dance tunes, for example, were brought not only in the 18th century by the Northumbrian/Lowland Scots/Ulstermen settlers of the backcountry, but also by the Wessexmen who settled the tidewater in the 17th century.

Also, some of the music the Puritans brought was simply the music of the English metrical psalter, and would not have been unique to the Puritans. The Cavaliers who settled Virginia would have had the same Old Version and New Version psalters that the New England Puritans had. Also, though New England was Congregationalist-dominated, there were other groups, including the Jewish community in Rhode Island.

I'd be cautious of assuming Spanish influence by way of Spanish Florida. Musical books printed in Spain might just as easily be a channel for any Spanish influence that might be detected.

For a tranmission vector for African influences I would look to the revivalist awakening of the 1830s.

Some of the "Swedes" who settled the Delaware valley were actually Finns, or so I have heard. I don't know if that is musically significant.

T.