One theory is that the Walnut Grove Prestons descended from the Gormanston Prestons. A researcher put together a chain of events for my parents that showed John Preston was a son of Jenico, the 10th Viscount of Gormanston and from there traced his history back to about 1360. There is however a problem with the dates. Jenico, the 10th Viscount Gormanston, died in 1757 and was succeeded by his eldest son, Anthony the 11th Viscount who was born in 1736 (according to Burkes Peerage and Baronetage). John who was supposed to be a son of Jenico was born in 1726 and was not the eldest. Actually, the John, son of Jenico, was born in 1742. Not likely to have a son born in 1750, Robert Preston. (Another problem with the Gormanston theory is that they are catholic and the John Preston from northern Ireland was Presbyterian, Scots-Irish.) Therefore, I will have to start the Prestons of Walnut Grove with this John Preston, b.1726, parents currently unknown.

Most researchers indicate that the Walnut Grove and Smithfield Prestons are related, but the connection is not known, at least not to me. There are or were Prestons located in Scotland who were lairds of Craigmillar for almost 300 years. There was a Sir John de Preston of Gorton (Scotland) in the 1340's. There are numerous branches of Prestons in England including Preston-Patrick, Under Levins Hall, Holker Estate, Furness Abbey, Cockerham Estates, UpOttery, Devonshire, Askham Bryan Hall, Flashby Hall and Moreby and Dalby Park, Lincolnshire. These lines are mostly unconnected or at least I don't have the connection. Also, separate from these are the Gormanston Prestons and an off shoot called the Swainston branch, both of County Meath near Dublin. With all of these Preston families in Scotland, England and Ireland, it seems unlikely that someone decided to call themself Philip Preston and come to America and settle in Bedford County, Va, or call themself John and become either the Walnut Grove or Smithfield Prestons. All three Virginia lines started between 1740-1773. The New England Prestons started in the early 1600's and there is speculation that at least one branch was descended from the Askham Bryan Hall of Flashby and Moreby in Yorkshire. More than one unrelated person could have taken the Preston name, however it would seem likely that there are many connections to be found in all of these families.

 The coat of arms of the Gormanston Prestons: Or on a chief, sa., three crescents, gold. Crest-on a chapeau, gu., turned up, erm., a fox passant, ppr. Supporters-Dexter, a fox, ppr.; sinister, a lion rampant, or. Motto-Sans tache (without stain). See Preston Arms.