I have been working my way back in time and records and have traced the paternal line of Pieter Koole (the immigrant) to his great-great-great-grandfather Pieter Koole and his wife Lijsbeth Robbereghts in Zonnemaire, Zeeland, married 1702. That would make this Pieter Koole my 7th Great grandfather (or great-great-great-great-great-great-great-grandfather). Pretty cool, huh? I have copies of baptismal records and marriages for each of these generations (civil records for those after 1811, personal records for those after 1900). The church records from the 1700s are from microfilm of copies made in the 1918-1920 time frame. Apparently the originals were sent to the provincial archives in Middelburg, Zeeland and were destroyed in bombing in World War II. I am trying to learn more about this, but have yet to find any English accounts. So far my Dutch is only fair and I'm not too good at translating some of the more detailed websites. (I dropped out of Dutch class this year!!)
There is always the possibility that I made an error in linking people, or that the transcripts were in error. However, each of these marriages identifies the place and the baptismal records usually includes "getuige" (variously translated as witnesses, sponsors or godparents) who are usually parents and siblings of the birth parents. This helps to link families together. And, best of all for me - there is only this one cluster of the Koole family in town at this time - all tracing back to Pieter and Lijsbeth.
From this point, it will be more difficult. There are few earlier church records. And many records not online. Notarial records may help - for that I need to improve my skills with Dutch language and handwriting . And - in this particular case - Pieter Koole is identified as widower of Isabella Carels from "B op den Z." Have no clue where this is - possibly Brouwershaven, which is nearby and sort of on the sea? Thought possibly the larger city (now anyway) of Bergen op Zoom (I know of it from 20th century relatives living there) but is is some distance away. I do find some Carels family in Brouwershaven in what is now online, as well as in Zierikzee, but will need to do much more searching. Lijsbeth is from Zierikzee - it will be quite a search to try to find her parents.
Another problem getting back this far is that surnames are less common. Sometimes records only use a given name and a patronym (father's name). This is wonderfully helpful when the patronym is included as a middle name with the family name (as is the case with almost all of these generations of Kooles) but so far I have not found the earliest Pieter with any other identifiers. No patronym, no occupation, nothing other than the one reference to "from B op den Z." None for Lijsbeth either (although at least that is a less-common given name)
And, the time consuming part - when searching online records or indexes, I have to try many spellings. Robbereghts, Roberechts, Robrechts, etc. as well as all the K/Co(o)l(e) spellings!!!