The surname McClendon in my family has been credibly traced back using both documentary and DNA evidence. It is Irish (not Scottish as often conjectured) and connected to several existing families in Ireland. The name has many variant spellings such as McLendon.
The North American branches of our McClendon family can be reasonably traced back to the immigrant Dennis McClendon (with spelling variations). Although precise lines of descent aren’t always known, geography, naming patterns, and land record evidence all point back to Dennis. DNA evidence backs this up as well. The earliest document showing Dennis’s presence in America is a 1697-01-11 North Carolina record, and prior to that he was across the border in Virginia probably by 1687 at the latest.
Dennis’s father was almost certainly Bryan Macklendon (again, many spelling variations), a small plantation owner in Barbados. Dennis may have been born there. Bryan’s will, dated 1687-12-29ref, mentions only a single child, Dennis, who had moved away. Dennis named his oldest known son Bryan.
Not much is known of the elder Bryan. His age was stated to be 30 on 1660-03-27, placing his birth around 1630. He was almost certainly Irish (and not Scottish, since a Scot would not be expected to be in Barbados) and probably immigrated to the colony. Some have suggested he came as an indentured servant, and upon gaining his freedom came to own a plantation of his own. His son chose to leave rather than continue to maintain the plantation, so Bryan’s fortunes may not have been great. Bryan’s wife was named Margery, and may have been the daughter of Henry Hunt. Bryan died in 1688, and Dennis travelled to Barbados in 1690 to claim his inheritance and then returned.
The line of descent to my traceable ancestors John and Nancy McClendon has not been definitively established.
The Y chromosome is passed from father to son identically, excepting small mutations, and thus can be used to trace a patrilineal line. This can confirm documented lines, confirm shared surnames are related, and reach into the past beyond them.
Dozens of McClendons have gotten DNA tests, most of them descendants of the immigrant Dennisref, and some from wholly different branches.ref Nearly all are STR matches to each other, confirming these families descend from a single individual in the distant past.
With increasing testing, more precision has been gained in identifying the McClendon haplogroup. Here are some representative groupings of increasing specificity that testees have been identified as:
R1b (M343) > M269 > L51 > P312 > DF27 > A431 > A432 > BY164509 > BY166389 > BY166781
There are more recent SNPs found, but they appear to be within the McClendon family, while the last one appears to be common to all these testees. So we’ll provisionally say this family is in haplogroup R1b-BY166781 (alternatively written as R-BY166781).
Tests have been done of people with similar names from Ireland or of recent Irish descent. Those with Irish surnames McLinden, McAlinden, and Linton have been found as matches to our McClendon family, showing a relationship between these families several centuries back. This has also been interpreted as confirming descent from the ancient Mac Giolla Fhionntáin.ref
Tested surnames that have not matched include McClelland, McLellan, McCleland, and so on; McClenny and Clenny; and even other families with the name McClendon.ref Many of these trace back to Scotland, further indicating that our McClendons do not derive from there.
Many autosomal matches confirm my relationship to at least some McClendons, but one match most clearly connects me to the larger family.
A male-line (named McClendon) descendant of Thomas Jefferson McClendon, son of Dennis and Mary McClendon, is an autosomal match to me, and, more importantly, my mother (at 67 cM) and my maternal aunt (72 cM), both large matches. He is their third cousin. Furthermore, he has been tested as in Y haplogroup R1b-L51, which is consistent with the above haplogroup; 23andMe only tests a few SNPs and so cannot narrow it down further. L51 is a large grouping, so coincidence can’t be ruled out, but with all the other evidence it is quite unlikely.
Hence, these matches confirm my descent all the way up the McClendon line into the deep past.