We were at a wedding last night. The grandfather of the bride - Menachem - read a blessing written by his great grandmother's great grandmother to her daughter, when she married; it has been read to all of the generations since. That's ten generations from the original author to yesterday's bride.
The author lived in Emden, Germany, in the 18th century. The sixth generation was the last married there: Menachem's parents, both murdered by the Germans; Menachem and a brother were the only survivors. I don't know how the document survived, but of course, Menachem's mother didn't read it to him when he got married.
The young couple has four sets of grandparents. One set from Germany, two sets from Yemen (one on each side), and one set from Iraq. If one assumes four generations per century, that's something like 60-100 generations since the Iraqis and the Germans were last likely to have intermarried. The rules of the ceremony we saw yesterday were hammered out in Erez Yisrael and Iraq about 60-70 generations ago. The Yemenites could easily have been separated from the rest as long ago as 120 generations.
These are miraculous times we live in.