It is sort of a guess that John was the son of Isaac, there is no smoking-gun proof. Actually for a long time I had a theory that he was the son of Johannes Mertz who moved from Longswamp Township, Berks County to Mahanoy Township, Northumberland County in about 1810 and had a known son John born 1801. But when I was able to track that other John down and he did not go to Ohio, I cast about for a different theory.

Here are a few facts that support the theory that John was the son of Isaac.

It is known that he had lived in Middleburg, PA previous to moving to Ohio. In fact, we’re quite sure he was the John Mertz living there in 1830 near Samuel.

His wife was Sarah Harmony and the place where we find people named both Mertz and Harmony in the 1820 Census was New Berlin, PA.

If John was of, let’s call it the (now) Snyder County area, then based on his age he was a grandson of either Nicholas or Philip, the two pioneer Mertzes of Snyder County -- Nicholas settled in Middleburg in about 1790, Philip in Freeburg. They are also the part of the Longswamp family for whom the Mertz spelling was retained and it was the Mertz spelling that carried to Ohio (for John, anyway, if not anyone else).

I think I can rule out Philip as his grandfather based on what I know about his sons and if Nicholas was his grandfather, then the best candidate, maybe the only candidate, was Isaac.

John named his first son Isaac. I believe John was Isaac’s oldest son and he is designated P5a1.

THE AUGLAIZE, OH MERTZES. A letter to the Snyder County Historical Society on file there alerted me to the fact that a John Mertz (4 Jun 1801-1 Mar 1877) married Sarah Harmony born 23 Oct 1803 and moved to Auglaize County, OH around 1850. All their children were supposedly born in Middleburg including: Benjamin Franklin (1835), James Davis (1837), Archabald T (1830), William, Isaac, Emma Rebecca (1847), Perry and Elizabeth. Indeed the whole family just as the letter writer said was present in the 1850 Census in Auglaize.

1830. John Mertz age 20-30 lived in Middleburg, PA. He was a neighbor of Samuel Mertz. He had 3 sons under age 5, and 1 age 5-10.

1850 Census. John Merty, age 49, lived in Union Township, Auglaize County with Sarah 47, Archabald 20, Franklin 15, James D 13, Elizabeth 8, William 6 and Emma R 4.

John was still present in Auglaize in 1860 and 1870.

The problem is where was John in 1840? One of his descendants believes he may be the John Martz in Norwegian Township, Schuylkill County in 1840. That John was age 30-40 as was his wife. Notably, he had 7 sons including 3 who were age 15-20. I cannot really make those head counts of sons work with what I know about John so I’m not sure this was the right John. However, I don’t know who John of Norwegian Township was.

The author of that letter identifying this family was Robert E Mertz (born 1918), son of Walter H Mertz (1892), son of Archabald Henry (1867), son of Archabald T.

Over the years, I worked from time to time with descendants of John and Sarah to determine who this John was. I always had a theory about it because his supposed birth date 4 Jun 1801 was so remarkably close to John, about the last Mertz born in Longswamp, who was born 6 Jun 1801 according to church records. One of the reasons I found this theory plausible was that I could not account for John from Longswamp after about 1820.

Later, when another descendant of John of Auglaize joined the Mertz/Martz DNA project, and his DNA proved that the Auglaize family was absolutely descended from the Longswamp Mertz family -- ruling out all the other various unrelated Mertz or Martz families -- I was sure my theory was right. Of course, the DNA only proved descent from John David, it did not actually narrow down in any way which line.

But my whole theory came tumbling down when it became absolutely clear that the John born 6 Jun 1801 in Longswamp moved by 1840 to Jefferson County, PA where he lived out his life.

Once I had determined that John of Auglaize was not John born 1801 in Longswamp who later lived in Mahanoy Township, and I was casting about for a new theory on who John’s father was, a long-time correspondent, Mary Mertz, who now lives in Iowa and whose father had submitted the DNA that proved that the Auglaize family was of the Longswamp family, suggested possibly Isaac of Middleburg then New Berlin if for no other reason than Auglaize John had named his first son Isaac.

I came to really like this new theory and it is now what I believe.

Nicholas of Middleburg and Philip of Freeburg were the original two Mertzes who moved from Berks County to what is now Snyder County. I think I know all of the sons of each because Philip left a detailed will and after Nicholas died, there were extensive Orphans Court filings that seemed to name all his children.

The Robert E Mertz who wrote the letter about the Auglaize Mertzes seemed to want to focus on either the sons of Nicholas of Middleburg or Philip of Freeburg as candidates to be John’s father. He didn’t seem to know the names of Nicholas’ sons so in fact focused moreso on Philip’s. Since Philip was my line, I pretty much could rule out the possibilities Robert was interested in and I guess my mind wandered away especially focused (erroneously I now believe) on the near coincidence of the birth date of John of Auglaize to the wrong John born in Longswamp. Mary was now bringing me back to consider Nicholas’ sons.

The letter writer did say that death records of all of the children of John of Auglaize said each had been born "around Middleburg". I have the death certificate of James Davis Mertz, son of John, and it only says Union County (which it would have been when he was born) though not specifically Middleburg. But that doesn’t rule out Nicholas, in fact keeps him quite alive as the best candidate.

When I was first tracking this man, I found there was a John Mertz living in Middleburg in the 1830 Census who I presumed (and now still believe) was John who would later move to Auglaize. At the time, I hadn’t yet located the other John who actually was living in Little Mahanoy Township so I was willing to believe that John of Mahanoy had moved to Middleburg possibly because he knew cousins there.

So everything points to Nicholas of Middleburg as John's grandfather, the next question being which of his sons was John's father? By the way, a strong clue here should have been that the name in Auglaize was spelled Mertz and I have observed many instances where someone moved that Mertz evolved to Martz but I have not seen any instances where Martz evolved back to Mertz. The other John was already spelled Martz once he moved from Longswamp to Mahanoy.

So the ages of some of Nicholas's sons can only be estimated from various documents but I think I have a pretty good idea for all of them.

The three oldest sons, and the only candidates, were Isaac (born 1777), Abraham (1780) and Jacob (1781). All of their birth dates are known from Longswamp Church records and it is clear from Orphans Court filings after Nicholas' death that his other sons were a good bit younger.

Of these three, I could pretty quickly rule out Jacob who I know a lot about and who left a will naming all his children. He had a son John, whose full name was John Aurand Mertz, and John A is accounted for. He did not move to Auglaize.

Let's consider Abraham. By 1830 for sure (and now I know well before that), Abraham had moved to Pickaway County, OH and a neighbor of his in 1830 was John Martz -- probably the John Martz who married Rebecca Bowman in Pickaway in 1827 and also quite probably the John Martz son of Abraham's said to be living in Indiana when Abraham died and a petition was filed regarding his estate. So Abraham, too, had a son John, but I think he is also accounted for.

Isaac is now the last man standing as the single best candidate (and perhaps obvious one since, as Mary says, John named his first son Isaac).

Isaac left no will and there is no other document that I've ever seen that names his children. But because, by 1820, Isaac had moved to New Berlin, I consider him the progenitor of the New Berlin Mertzes and so as I would come across some other younger Mertz with a New Berlin connection, and if I had no other candidate to be their father, I would surmise they were Isaac’s son and have come to believe that, in that way, I have identified some of his sons.

In 1800, Isaac lived in Penns Township, Northumberland County. This is the area that eventually would become Snyder County and it included Middleburg at the time, Nicholas, his father, was also living in Penns -- meaning Middleburg per se was not a separate Census area. It would appear that Isaac was already married and had a very young son.

In 1810, Isaac lived in Swinefords -- the old name for Middleburg. He was married presumably and his household included 4 males under 10. Of the 4 sons I have identified that I believe were Isaac's, Samuel and Henry were born prior to 1810, the other two after. So there is room for two more sons who, assuming they survived, would need to be identified, one of whom absolutely could be Auglaize John.

By 1820, Isaac had moved to New Berlin. Now his household had 7 young males. I know from the death certificate of James Davis Mertz, son of Auglaize John, that John's wife, James' mother, was Sarah Harmony. A check of the 1820 Census for anyone named Harmony living, let's say, near the Susquehanna River finds just two -- both living in New Berlin.

By 1830, John -- who I now believe was the son of Isaac and who would later move to Auglaize, was living in Middleburg. While it would seem he had probably moved to New Berlin with his father, the family still had some ties to Middleburg -- his uncle Samuel for instance was still there. So John appears to have gone back to Middleburg (not a very far distance).

This John in Middleburg had 3 sons age under 5 and 1 slightly older. So the tick marks do not really make sense if we thought it was the other John whose sons Daniel and Elias would both be 5-10. It maybe fits Auglaize John although from what I know his son Isaac would have been the one 5-10 and I only know two additional sons -- Perry Oliver and Archibald — who could be two of the three under 5.

In looking through my files again, I also saw that I have a typed piece of paper titled Auglaize County Democrat (the newspaper). I imagine it was part of what the letter writer sent to the Snyder County Historical Society with his inquiry. It is a summary of John's obituary saying he died 1 March 1877 in Wapakoneta and was 75 years, 8 months, 17 days old. It also says he was born 4 Jun 1801 but isn't it interesting that the age as stated computes to either 12 Jun 1801 or 14 Jun 1801? Take your pick of those.

To summarize.

I now believe the best candidate we have to be the father of John of Auglaize is Isaac, son of Nicholas. But it is just a theory -- there is no smoking gun proof.

John is on find-a-grave. His wife and seven of his children are linked to him.

His daughters were listed by the letter writer.

His sons were listed by the letter writer and I have found all of them in the 1850 or 1860 Census in Auglaize. All except for Isaac are linked to their parents on find-a-grave.

Isaac (P5a1a) was head of his own household in 1850.
Perry Oliver (P5a1b) is elusive in 1850 but lives in Auglaize as head of household in 1860.
Archibald (P5a1c) was living with his father in 1850.
Franklin (P5a1d) was living with his father in 1850.
James D (P5a1e) was living with his father in 1850.
William (P5a1f) was living with his father in 1850

The death certificate of James Davis Mertz says he was born in Union County, son of John Mertz and Sarah Harmony.

Sarah is on find-a-grave.