I would estimate, based on the (in some cases) estimated dates of birth of their children that Nicholas married Catharina about 1775. His wife was always named Catherina, in three baptisms of their children at Longswamp Reformed, and then as administrator of his estate when he died in 1801.

We know the dates of birth and death for Catharina from her tombstone at Hassinger’s Old Cemetery, Snyder County, PA.

The will of Martin Cleaver of Hereford Township, Berks County dated 12 Jun 1797 and proved 28 Feb 1799 gave one half of his estate upon sale to eldest daughter Catharina and husband Nicholas Mertz.

So it all seems straightforward, Nicholas’ wife was Catharina Cleaver. However, it must be remembered that there was another Nicholas of Longswamp and I have seen some mention somewhere that Nicholas’ (who knows which one?) wife was named Catharina Folk, but I have never seen any hard evidence that that was the case.

But with no hard evidence to contradict the straightforward conclusion that the wife of Nicholas of Middleburg was Catharina Cleaver, I am stating that as the case — until and unless some other evidence comes along to make me re-think things.

In 2019, I revisited this question of whether we could consider it “proven” that Nicholas’ wife was Catherine Cleaver, daughter of Martin, so I read his will and estate file again. And I realized that Nicholas’ other daughter was Mary, deceased wife of Martin Eisenhower. Remember, Sarah (Salome), Nicholas’ daughter, married Peter Eisenhower.

I didn’t do much work on this but I did find an Ancestry tree (note I generally do not trust such things) that shows a Martin Eisenhower of Hereford Township who had a son Peter with these additional supposed facts: Martin’s wife was Sarah (he may well have married again after Mary died), nothing more was shown about Peter including no wife was named but they did have his exact birth and death dates as I have for Peter.

Now understand, the person who built that tree may have it right that Martin had a son Peter but maybe it was a different Peter and they didn’t realize that when they picked up the birth and death dates for the wrong Peter from find-a-grave.

My conclusion is that while I don’t fully trust the Ancestry tree which would seem to indicate that Sarah Mertz married her cousin Peter Eisenhower, I think the coincidence of the Eisenhower name as Catherine’s maiden name and the name of the man her daughter married is some additional evidence.

In 1810, Catharin Mertz widow age 45+ lived in Swinefords, Northumberland County. Son Isaac was nearby.

In 1820, Catherine Mertz age 45+ lived in Middleburg where her son Samuel also is found.

A Nicholas Mertz died in 1801 in Middleburg, (then) Northumberland (now) Snyder County, PA. Based on all the research I have done on the Mertzes of Longswamp Township (Berks County) taken together with what I learned about Nicholas of Middleburg (timing of his first appearance in Northumberland County, name of his wife, names and birth dates of his children), there can be no doubt he was of the Longswamp Mertz family, and from his age, of what I call the third generation (David, the immigrant, Gen I, his sons Nicholas and Hans Peter Gen II).

But the question is how many third-generation Nicholas Mertz were there in the Longswamp Family -- one or two? And if two, which one of them came to Middleburg?

Nicholas of the second-generation died in 1760 and from Orphans Court records after he died, he definitely had a son Nicholas. Then when Hans Peter died in 1787, he named Nicholas as one of his Executors. Was that his nephew or did he too have a son Nicholas?

Charles Fisher, noted Snyder County genealogist, identified Nicholas of Middleburg as the brother of Philip who came to nearby Freeburg, who, no question was the son of Hans Peter. Philip and Nicholas were both Lieutenants in the Berks County Militia. They appeared in early tax records of Penns Township about the same time. So, the idea they were brothers made sense, but maybe they were just close cousins. How could it be known which relationship was true?

One question was finally answered when Mary Lou Kueker convinced me that Peter indeed had a son Nicholas as she found the proof. There were several deeds recorded not long after Peter’s death, wherein Peter Jr. and Nicholas sold their deceased father’s land. The deeds could not be more clear. Hans Peter had a son Nicholas.

The question remained, which one came to Middleburg? And while assuming Nicholas and Philip were brothers was logical, I wanted more proof. I feel the answer to that question can be inferred from the birth date -- 1748 -- of Middleburg Nicholas, from his tombstone.

The 1748 birth date is important because if you read all the petitions filed upon the death of Generation II Nicholas, his son Nicholas was consistently listed last among his children. Moreover, there were seven minor children when Nicholas died in late 1760 -- meaning they were born after 1744 (if minors were those under 16). So 1748 seems too early for the birth of the youngest of his seven minor children.

My conclusion is that Fisher was right all along, that Nicholas of Middleburg was the brother of Philip of Freeburg -- both sons of Hans Peter.

Curiously, Nicholas is unique among the seven sons of Hans Peter in that I know his birth date. For all the others, I have had to estimate their birth year based on things like when they first were listed as a single man on the tax records of Berks County, though that is an estimate at best since the tax records are sporadic as to which years were lost and which still exist. My best guess is that Nicholas was the fifth oldest son of Hans Peter.

As such he is designated P5.

THE MIDDLEBURG MERTZES. In 1789, Nicholas moved to what would become Franklin Township, Snyder County, near what is now Middleburg. Of all the Mertzes who came to then Northumberland County by 1790, it was only Nicholas and his brother Philip who ended up west of the Susquehanna River, the others stayed east of the river. Philip was living on the west side in 1790 too, but was omitted from that Census altogether. Four of Nicholas’ neighbors in 1790 all have the name Swineford. In 1810, his widow will be found living in Swinefords -- the town that later will be called Middleburg.

This geographic separation may well be the reason that the Mertz spelling was retained for Nicholas and Peter and their descendants (except in some cases for those that later moved elsewhere). The brothers who settled on the east side of the river came soon to have their name spelled Martz and basically all of their descendants today use that spelling.

1779. Pennsylvania Septennial Census. Nicholas Mertz, Hereford Township.

1790. Nicholas lived in Northumberland County, unspecified township, but he seemed to be quite separate -- geographically -- from all the other Mertzes listed.

1800. Nicholas lived in Penns Township, Northumberland County. Three other Mertzes were listed in Penns: Nicholas’ son Isaac, brother Philip and nephew Peter. Penns Township at the time was roughy the part of Northumberland County that eventually became Snyder County.

Nicholas’ grave was found and transcribed many years ago. Valerie Mertz found it more recently but it is unreadable today.

All the transcriptions and biographies I have ever seen for Nicholas are in agreement on his vital dates. “On Wittenmeyer Farm, Nicolas Mertz geb 8 Aug 1748 gest Horning (February) 1801 52y 6m 2w”. The arithmetic suggests he died 22 February 1801.

A 1748 birth date seems inconsistent with what I know about the other Nicholas, son of Nicholas, and I think rules him out as Nicholas of Middleburg and adds more evidence that there must have been two men named Nicholas of the third generation and this one, son of Hans Peter, came to Middleburg.