The fact that Peter's wife was named Catherine is known from her tombstone which is next to his, from his will and from her presence in the 1850 Census when she was living with a daughter. Jack Mertz referred to her as Catherine Moats. J L Floyd and Joseph Meiser both say she was Catherine Motz. The spelling doesn’t matter, all sources agree on her name.

The problem is I can’t absolutely prove that from any real document.

If that was her name, then I believe her father was George P Motz. The Motz and Mertz families were next-farm-over neighbors. George Motz said he had five daughters in his will but only three of them can be accounted for by name. From the wording in his will, we also know that the two he did not identify by name were married. Peter and Catherine’s marriage date is not known but can be approximated given their ages and ages of their children. George died in 1806, well after Peter and Catherine would have married.

Moreover, Catherine and Peter were buried immediately behind George’s son John Motz at St. Peter’s. Finally, George P Motz was George Peter and Catherine named a son George Peter Mertz, the name George theretofore not a Mertz name (in Hans Peter’s line).

So, all evidence is that she indeed was Catherine Motz, as suggested by those other early genealogists.

But that ’s where I was stuck, believing I knew who she was but without really strong evidence, until in 2020 I undertook a serious study of my autosomal DNA test results (I did the test in 2019).. And I now believe that DNA evidence strongly supports the idea that Peter’s wife was indeed Catherine Motz, daughter of George Peter Motz.

I discuss the findings in more detail under the heading “DNA Evidence” for Catherine and in the database record for her father, but briefly:

I have far too many DNA cousins who can only be my cousin because they descend, not from Catherine, but from George (one of his other children), or from a (presumed) brother of George or most strikingly, from a woman definitely named Motz who was, I believe, George’s aunt. Catherine was definitely a Motz.

Was George Peter her father? Well, DNA doesn’t prove that — but he is so obvious a candidate it must be the case. He was exactly in the right place at the right time. And while his (presumed) brothers lived for a period of time in the same area, they moved away before Catherine was “of age”. So any scenario for anyone else to be Catherine’s father except George Peter would be a real stretch.

And so the real issue now is who was George Peter’s father? We know the father of the other two persons who came to Penns Township at about the same time as George Peter and I can build a very strong logical case that the they were brothers but hard documented evidence of that fact is lacking.

DNA has convinced me that I do descend from George Peter Motz and that Catherine, wife of Peter Mertz, was his (George Peter’s) daughter. My first attempt to analyze this was to examine trees of people who had someone named Motz in their tree, verify that I could see no other way I might be related to that person (doesn’t rule it out just means it’s not obvious if there was). And then see if I recognized the Motz they do descend from.

Now the big flaw in the way Ancestry presents to people who they may descend from based on who they share DNA with, especially as presented by them in their Thru-Lines presentation is this: If I share DNA with someone else who descends from, in this case, Peter Mertz and his wife Catherine, and if that other person has her in their tree as Catherine Motz, daughter of George Peter, then Ancestry tells me that I may descend from George Peter Motz, as if DNA is suggesting that. No, it would only be that my “cousin” is suggesting that with what may be erroneous information in their tree.

But that is not what I am finding in this particular case. It is not that I share DNA with someone who descends from Catherine and who claims she was Motz — it’s that I share DNA with people who do not descend from Peter and Catherine but who seem to descend from either her father or some other close relative of his.

When I first did this, I found two DNA cousins, who both have Motz in their family tree and their connection is not through Catherine and Peter Mertz. One of them descends from George Peter’s son (Catherine’s brother) John and one of them descends from Michael Motz who likely was George Peter’s brother. I have closely examined the trees of both of these two people and see no other way I would be a cousin to either of them.

Now it could be for example, the person who descends from John Motz shares some other ancestor in common with me not named Motz and not descended from Motz. That can never totally be ruled out which is why part of my approach is to study their full family tree to see if I can detect any other possible connection. In both these cases, I couldn’t.

But then in 2020, I came into contact with two Motz researchers who had been collaborating on all things Motz in America. I found them both to be my kind of researchers — believe only what is documented with real evidence but be open-minded to all the possibilities for things that cannot be 100% documented.

With their help, I came to understand that I had several dozen DNA cousins who had Motz in their tree who previously I just didn’t know who they were or how their Motz ancestor may have been connected to mine.

The most interesting thing I learned from these Motz researchers is that the Motz family of America (well many of them, mine for sure) were direct descendants of the Motz family of the Lampertsloch area of Alsace. This area is not far at all from where my Mertz ancestors came from. Did Peter Mertz and George Peter Motz, neighbors in Freeburg, know that their grandfathers were from about the same place? Did Peter Mertz and Catherine Motz know they shared the same Alsace ancestral home?

What convinces me (and them) of this is I am a DNA cousin to close to a dozen people who descend from Matthias and Anna Catharina (Motz) Nehs. She is the sister of Heinrich Motz who was the father of Michael Motz, presumed brother of George Peter.

This story continues in my database under the DNA Evidence heading for Catherine’s father, George Peter Motz.

Since for a time, I wasn’t sure Catherine was maiden name Motz, I did look for any other clues that might lead in a different direction. Peter and Catherine had 4 sons: Philip P, John P, Peter P and George P. I know that my ancestor George P was George Peter Mertz, as stated above, perhaps named for Catherine’s father. But over the years I have pondered this coincidence of four children being given a middle name starting with P.

I wondered one-time whether Philip P maybe was Philip Peter and Peter P was Peter Philip and then for balance maybe John P was John Philip. Two middle names Philip for their one grandfather, two middle names Peter for the other.

At another time, I joked that Peter (the father) maybe loved his own name so much that all his sons had the middle name Peter. That seemed a little absurd though as that would mean his third son was named Peter Peter Mertz.

And then I found the death certificate of Rev John Allen Mertz, son of Peter P. The informant was John Allen’s son Paul. He very deliberately and very carefully wrote the name of his father as Peter Peter Mertz.

And then it hit me. I have seen in other Mertz families, that by the 1800‘s, naming conventions had evolved. No longer was it that almost every male was Johann plus a middle name -- and then went by their middle name. What happened instead, in quite a number of families I have seen, is that almost all the children were given the same middle name -- the maiden name of their mother. Could Catherine have been Catherine Peter? I am related to the Peter/Peters family of Lehigh County and a few of them had moved to Northumberland County, in fact, Penns Township, by 1790.

So I tried to research the various Peter families of Northumberland County to see if there was any additional evidence for this alternate theory. I could never find any.

Catherine is on find-a-grave.

Peter was likely baptized at Longswamp Reformed Church but his baptism went unrecorded. But we know his birth date from his tombstone And we can be sure he was Philip’s son because Philip named a son named Peter in his will and he was a neighbor of his parents in early Census listings. Jack Mertz, J L Floyd and Joseph Meiser state that he was Philip’s son.

He is designated P4a.

He was born while his parents were in Longswamp Township; they were active in the Reformed Church there in a period when the records of that church appear to be complete and yet Peter was not listed among the recorded baptisms. (There were other Mertzes too either not baptized or whose baptisms went unrecorded.) He moved to Freeburg from Berks County with his parents in about 1785 and there grew up to marry the girl next door -- literally. And there he lived the remainder of his life.

The 1830 Census has me puzzled. Two men named Peter Mertz lived in Washington Township. One was listed immediately above Philip Mertz, Peter’s son, and has (almost) the count of persons by age bracket I would expect. That listing has these people. A male 5-10 (George Peter), a male 10-15 (Peter P) and a male 50-60 (Peter age 56), a female 10-15, another 20-30 and one 50-60 (Catherine age 54). I do not know the ages of all of Peter’s daughters nor when they married, so the female headcount is reasonable but I’m not sure which daughters remained and which had moved out.

The other Peter I cannot identify. He is listed just below Henry and they are a few names removed from Peter and Philip. My hunch is that he is Henry’s son, but the list of Henry’s children as given by Meiser (Martz/Mertz) does not include any son named Peter. There are four persons in this household: males ages 20-30 and 50-60 and females ages 15-20 and 40-50. My thought is that the younger male is Peter, that perhaps his wife is just 19 and that the older people are his in-laws. This is all speculative, and I may well be wrong about who this man was -- but in any event, the other Peter is my ancestor.

This may be related to the mystery of Philip’s daughter Anna Mary who supposedly married Peter Mertz -- I do not know who that Peter Mertz was either.

Peter is on find-a-grave.