That is not so uncommon in Europe. Both from my maternal and paternal line the oldest ancestors I am aware of lived almost 400 years ago, in the mid 17th century. Before that the registers from my region are very patchy, because of the devastations of the Thirty Years' War. Were this is not the case, it is not uncommon that one is able to continue the line back to the 16th century, especially for people living in towns (not to speak of the aristocracy).

Or, as another example, here is photo of the reunion of the "descendants and sides relatives of Dr. Martin Luther and Katharina von Bora" (not related to myself): https://www.lutheriden.de/the-lutheriden.html

Very common to be able to do this in Europe. I've traced my family back to the early 1500s via Ancestry.com, and my family tree isn't anything special. Before that period, records get very sparse among the common folk, though, and you pretty much need to have a strong connection with nobility to go further back in time.

...and so on.

https://www.sciencedirect.com/science/article/pii/B978032399...

From the methods section:

> Nuclear DNA in hair has an extremely low average fragment length owing to the activity of endonucleases expressed during hair formation.

But the researchers made adjustments for that during sample prep before sequencing, and alignment after sequencing.