NameCatharina 
Birth1774
Memo(age 75 at death)
Memo(1850 Mortality Census)
Spouses
Birth1776
Memo(1860 Mortality Census)
Memo(1860 Mortality Census)
Parent-Proof notes for Catharina
Theobald’s wife was said to be Catharina when he baptized son Theobald in 1800. But his daughter Catharina born in 1807 was said to be the daughter of Dewald and Magdalena. I could pose the idea that Catharina died and then Theobald married second Magdalena but then who was the Catharina who died in Oct 1849 in North Whitehall?
Census shows that Theobald’s wife of a similar age to him was alive in 1840 and apparently had died by 1850. Was her name Catharina Magdalena? (Unlikely, but I have no better solution.)
Birth, Parent-Proof, Designation notes for Theobald (Dewalt) (Spouse 1)
A man named Theobald (Dewalt) Mertz existed. He first was listed in the 1810 Census in Heidelberg Township and we know he was born in 1776. Because of where he lived geographically, from his age and from the fact that I have no better idea who he was, I have made Theobald the son of Philip who was older and lived in the same place. He is designated G1c.
In The History of the Counties of Lehigh and Carbon, Chapter XXIV covers Heidelberg Township and in addition to three mentions there of Philip Mertz, Dewalt Mertz was named once — on the 1812 tax list.
This area was Northampton County originally but in the area that would become Lehigh County. Dewalt was also named in the records of Schlosser’s (or Neff’s) Church in nearby North Whitehall Township and also at Lowhill Church in Lowhill Township. It is Dewalt’s connection to these other places (Neff’s and North Whitehall Township) that is the basis of my belief that certain others connected with these same places are of the same larger family.
Relocated and Census Tracking notes for Theobald (Dewalt) (Spouse 1)
In the 1800 Census, a William Mertz age 26-45 and a Philip Mertz age 45+ were listed in Heydelberg (sic) Township, Northampton County -- basically the same small geographic area as North Whitehall and Lowhill.
In 1810, Devolt Martz age 26-45 was listed in Census also in Heidelberg. He was still there in 1820 (by which time Heidelberg was part of newly formed Lehigh County) as Theobald Mertz, still 26-45. In 1830, he was Showalt Martz, now in North Whitehall Township, Lehigh County, age 50-60. Finally, in 1850, he was Dawata Martz still in North Whitehall, age 74, he lived with Morten (Martin?) Martz, his son I assume.
Death and Find-a-Grave notes for Theobald (Dewalt) (Spouse 1)
In a few decades of the mid-to-late 1800’s, a distinct part of the Census project was to ask whether any member of the household had died within the most recent 12 months. It is called the Mortality Census. Dewalt was listed in the 1860 Mortality Census as having died in the last 12 months and was age 84 at death.
Theobald is not on find-a-grave.
Theobald’s estate entered administration 15 Oct 1860. Tilghman Mertz was the administrator. I believe Theobald had two grandsons of that name so it’s not clear which one it was. There is mention in the inventory of a note from Gottlieb Stahly and another from Martin Mertz.
Discrepancies notes for Theobald (Dewalt) (Spouse 1)
Karen Brislin also told me that when Susanna baptized her own son, Tilghman, in 1837, the sponsors were “Adam Mertz, Rebecca”. This, I think, is a very strange anomaly. I have found evidence of a man named John Philip Mertz whose wife was Theresa — (exactly the names of the Carbon County couple I think were of the Heidelberg family) — but a totally different couple and Adam and Rebecca were related to that other John Philip who had recently arrived from Germany. Why Susanna had them as sponsors I could speculate on endlessly. The truth is I just don’t know.