Wilcomb E. Washburn, Virginia Under Charles I And Cromwell…
“ Virginia's most important frontier region in the 1650's was the area along the Potomac River, although settlement went on simultaneously westward up the James, York, and Rappahannock, southward into Carolina, and northward up the Eastern Shore to Maryland. Sometimes individuals obtained grants to explore, settle, and monopolize the trade of these regions. But usually the expansion was catch as catch can. Since land travel was still more difficult than water travel, expansion up the Potomac, the last great unsettled tidewater river, was fastest. ”
