Defreine
With the advent of DNA research and so-called "one-name studies", it is easy to confirm that males with matching surnames need not come from a common ancestry. The following information dates from a time when people imagined that a semi-matching surname not only meant a matching ancestor, but that the specific ancestor living a thousand years ago could be determined and thus must be someone historically important:
The name Defreine is of Norman Irish origin. There are many anglicised versions of the name - Frayne, Frenes, Freyne, DeFrayne, Franey, Freaney, Freeney, Frain, ffrench, Ffrench, French and possibly some more. All these names are the same and have been used, changed and interchanged over the years. All are derivatives of the same name “DeFreine”. Theophilus de Freyne, third cousin to William the Conqueror rode beside his cousin at the Battle of Hastings 1066.
The DeFreines, the ffrenches, and the Frenches, who were of noble blood, came to Ireland with Strongbow during the Norman Invasion of Ireland from 1169 to 1172AD. There were and still are two or three families of Irish peers who carry the names DeFréine, ffrench, and French. As Anglo-Normans the French family became one of the 14 Tribes of Galway, helping to found the town in 1425AD, fortifying it to keep the locals out.
In Wexford the name Franey is common, In Wicklow Freeney / Freney is common and in the Connaught area (Sligo/Galway) Frain, Freine are common. The name is from the French word Frêne which means a wooded place with ash trees indicating that ancestors of that family came from an area noted for its forests. Some sources can even trace the name back to Roman times.
Comments. The anonymous author treats the surnames French and FFrench as automatic matches to the surname DeFreine. Freine is said to refer to ash trees. The Middle English poem called Le Fresne by Marie de France perhaps could be cited, with Norman French invaders carrying the ash-referring name to the British Isles. However, individuals with the surname French need not have been of the French Normans, but could, as easily, have been named French due to being Germanic (Franks) or religious (followers of the lifestyle example set by Italy's St. Francis), perhaps arriving in England and Ireland earlier than did the Normans, perhaps bloodlessly, so with no historic battle records.
Sourceless Etymology.The anonymous author, who assumes all French and Ffrench track back to deFreine, does not cite a source. That further indicates that the notion of a common ancestor for Frenches and DeFreines is speculation. The best sources would be birth records. Yet, no solid, unbroken trail of birth records exists for everyone, dating back to the 1100s, when the Normans invaded England. As searches at familysearch.com or ancestry.com will show, few birth records before the 1500s survive outside of a myth/story form.
Male y-DNA. DNA makes this clear. A male DNA study of the surname French/Ffrench at one web site, begun in 2003 by David French and now administered by Julia French Wood, had reported, as of September 2014, over 50 distinct DNAs for the surname, so over 50 distinct, unshared ancestors. Add more individuals' tests for these spellings? Add other spellings? The number would rise, not shrink.
There are multiple DNA haplogroups for the surname. That is true for those French/Ffrench tracking back to Ireland, not just to Britain. The 50 different DNA stains collected by French and Wood so far include 25 "groupable" DNAs (multiple individuals tested and closely matching someone else in the same group, so apparently descending from a common ancestor, while not matching those for other groups), plus another 30 "solo" individuals that have not yet found any DNA match as too few tests have been submitted. The full variety can be seen at: https://www.familytreedna.com/public/french/default.aspx?section=yresults
It is good, however, to present the DeFreine example, as it illustrates how easily errors can be made in family genealogy if "too much" is believed. Speculation produces false family trees that erroneously span multiple DNAs, done in order to "magically" go back a thousand years, without birth records.