Rockland County is a wedge of farmland and forest only a few miles north of New York City. It's situated directly across the Hudson River from the legendary Tarrytown in Sleepy Hollow, the home of the Ichabod Crane and Headless Horseman. As with Sleepy Hollow, the Dutch first settled the Rockland County region, founding its many small farms and villages.

Although the Dutch surrendered to the English in 1664, for most of its history the area was dominated by families of Dutch and French Huguenot ancestry. Some of the families that moved into the vicinity in the late 1600s were named Tourneur, Oblenis, Low, Vleckerands, Hennion, van Vorst, Blauvelt, van Schyven, Baldwin, Onderdonk, Griswold, van Houten, and Lighthizer. Most of these families could easily be traced to the earliest days of the New Amsterdam settlement in the 1500s.

According to some 19th century genealogies, my wife, through her mother's mother's father, Russell Tenure (1892-1954), was descended from these old Rockland County families. However, using actual government and parish records, I could only really confirm the family tree back to wife's 4th great grandfather, Michael Tenure (1797-1863). While these old 19th century genealogies were written with great authority, they offered little corroborating evidence.

I was hoping DNA could provide us with that evidence when I first tested my mother-in-law's DNA on 23andme. Unfortunately, it proved very difficult to identify common ancestors with any of her genetic cousins, in Rockland County or elsewhere. There were a couple reasons for that problem:

1. The last few generations of her family were comparatively small. My father has hundreds of 3rd, 4th, and 5th cousins. My mother-in-law has a few dozen. Fewer cousins mean fewer close genetic matches, leaving only more distant relatives. It's much more difficult to find a 5th great grandparent than a 3rd great grandparent, especially when few people have complete family trees, including me.
2. My mother-in-law is 1/4 Jewish from her maternal grandmother's side. Some populations, such as Jewish people, have suffered through multiple "bottlenecks", where their population fell to a small number of individuals, which then intermarried. If your parents are 3rd cousins then your 4th great-grandparent is really your double 4th great grandparent, meaning that you share more genetic material with any of their decedents. This means that people of Jewish ancestry often dominate any list of genetic matches. Unfortunately, I am unable to trace that family branch back further than the mid 1800s, likely because of name changes.

Even though there were good reasons for not finding the common ancestors of genetic matches, I was beginning to worry that there was a mistake in the family tree or even that there was a non-paternity event. However, this latest Ancestry.com test has put my worries to rest, Ancestry.com is more focused on geneaolgoy and most matches have passable to excellent family trees. So, finally, I have matched some of her genetic cousins.

My wife has several genetic cousins that share Onderdonk, Blauvelt, and Tourneur ancestry in Rockland County and several other Dutch surname matches around New York. I've managed to find common ancestors for each of these Rockland families, although it is still difficult to claim any specific ancestor is confirmed by DNA. 

These families, along with several other old families in the region, often intermarried so it's sometimes difficult to define the precise source of the shared DNA. In one instance, I found a distant Blauvelt cousin who also shares Onderdonk ancestry, making it difficult to determine which of their common ancestors passed down the DNA. 

Still, I've confirmed that my mother-in-law is the quintessential New Yorker, whose maternal grandfather's family history reaches back all the way to the beginning of the New Amsterdam. That was certainly nice to put to rest. For once, those old 19th century genealogies were right.

So my wife's Ancestry.com DNA came back in. The first thing I looked at was her list of DNA-matched cousins, of course. The ethnicity results of these tests are quite broad and a little suspect but DNA matches are wonderful for confirming or challenging my family tree.

As I suspected, there was nothing obvious on her mother's side. My mother-in-law's family has been urbanites for a long time and tended to have smaller families. Additionally, half her family are recent immigrants (1850+), which means that they have fewer people testing. Americans are probably 90% of the DNA pool at Ancestry.com, which means we're not going to see a lot of Swiss or German cousins. 

However, there was some good results on her father's side, who has deep colonial roots:

William Nicholson and Telitha Thomas confirmed.
Thomas Thomas and Sarah (Eades?) confirmed.
Levi Ferguson and Rachel Collins confirmed.

All these were already confirmed by 23andme testing but additional evidence is always welcome.

Now to the more exciting bits:

I have several DNA cousin matches with John Thomas Collins and Nancy Curtis as the common ancestor. Rachel had a brother named Buford and a sister named Malinda, both of whom have descendants who share DNA with my wife.  In a previous post about Levi, I was unsure about the identity of Rachel's parents, although I had a decent guess. It turns out my guess was correct! Yay! 

In another previous post, I argued that Levi's parents were Robert Ferguson and Rachel Falls while every other family tree on Ancestry had Aaron Ferguson and Catherine Beck as his parents. DNA has provided me with more evidence that I was right. 

Rachel Fall's parents were John Falls and Rebecca Shields of Lincoln County, North Carolina. She had a sister named Sarah Falls, whose descendant shares a small segment of DNA with my wife. Pardon me while I perform my touchdown dance. 

We also have some matches with Levi's grandparents, James Ferguson and Sarah Barnet, and his great grandparents, Robert Ferguson, born 1722 in Scotland, and Elizabeth Wylley, born 1738 in North Carolina. 

There was one Rippey in the matches, which may confirm that line, but I can't find the exact common ancestor. There are a lot more matches, with whom I can't locate a common ancestor yet but who have good family trees. Perhaps some digging will uncover more matches. Also, in the next year, I hope to collect more spit from some earlier generations, which should really sharpen these results.