Re: Jetts, Washingtons, and Oxfordshire
One study of the English men and women who emigrated to Virginia during the middle of the 17th century (during the tenure of Governor William Berkeley) whose prior residence can be documented, shows that about 75 percent of them emigrated from the counties within a triangular region in the southern part of England (about 20 percent of the land mass of England at that time). The approximate radius of this area is on the order of 70 miles. The area of colonization of Virginia during this period was a roughly elliptical area, with a major axis radius of about 70 miles. I have seen graphical representations of both of these distributions. If the raw data from which these maps were made could be analyzed, it would be possible to construct probability distributions of both data sets and thereby determine the likelihood of two "random" families living within a specified distance of one another in England and in Virginia. Since I don't have access to the raw data, I can't precisely quantify the relationships. However, my guesstimate is that the probability of two random emigrant families living within fifteen miles of one another in both England and then later in Virginia in the mid 17th century is at least 20 percent.
All of the books on the Jett family that I have read make the obligatory reference to Thomas Jett of London, who was granted a coat of arms in 1709. Most of these books then go on to note that Col. Thomas Jett of King George and Westmoreland counties in Virginia used a "similar" coat of arms on a letter in 1774. What all of these books fail to acknowledge is that coats of arms can only be borne (in some form) by agnatic descendants of the original grantee, not distant cousins. There is at least one academic study of the market for false armorial bearings and false genealogical research in the colonies in the 17th century. It is my guess that the "similarity" of the coats of arms of the two Thomas Jetts was the result of something of this sort.
Jeter Jett's book, "The Jett and Allied Families," mentions John Jett of Coventry, England (fl. 1531-1542), Alexander Jett of Somerset, England (fl. 1622-1650), and Thomas Jett of Saxony (fl. ?1620, great-grandfather of Thomas Jett of London, granted arms in 1709). The date of birth of the immigrant Peter Jett is not known. However, since he apparently arrived in Virginia by 1666 with a wife and four children, it is likely that he was born before 1640.
Alexander Jett of London and Somerset is known from extant parish registers to have fathered at least two children, Anne in 1623 and Alexander in 1626/7. Clearly, this Alexander Jett was old enough to have been Peter Jett's father. It is also probable that either the grandfather or great-grandfather of Thomas Jett of London would have been old enough to have been Peter Jett's father. However, during the 17th century it was very common for English families to name either the eldest, or second eldest, son after the paternal grandfather. While Peter Jett may have had other children who died prior to his emigration to Virginia, the available records indicate that his two eldest surviving sons were William and Peter. Since there are no descendants of Peter Jett in the first several generations named Alexander and no descendants named Thomas until the 5th generation (great-great-grandsons of Peter), it seems highly unlikely that either Alexander Jett or one of the Thomas Jetts was Peter Jett's father. It appears more likely that Peter Jett's father was "a" William Jett. The only surviving parish register that I have located for a William Jett of about the right age is the christening record of William Jett in 1638 in Saint Botolph Bishopsgate, London, England to parents William and Elizabeth Jett. This William Jett "might" have been the father of Peter Jett, but clearly there is no extant record of Peter Jett's birth, so this is mere speculation on my part.