I am not researching this family, but have a book with some information on this line.From "Pedigrees of Some of the Emperor Charlemagne's Descendants" by J. Orton Buck and Timothy Field Beard:
"Jonathan Garrison of Accomack Co., VA, (was) son of Archibald Garrison of Accomack Co., and his wife, Kesiah Floyd, dau. of Berry Floyd of Hogg Island, Northampton Co., VA, and his wife, Esther Dalby, dau. of Branson Dalby, b. in Accomack Co., VA, 4 Dec 1774, d. in Worcester Co., MD, ca 1812."Jonathan married "Nancy (Anne) Selby, b. in Worcester Co., MD, ca. 1789, d. at Greenwood, Sussex Co., DE, 28 July 1855."
Please see the entries I just made in the Garrison and Wright Forums on the some of the lines down from this couple, and back from Nancy Selby to Charlemagne.