If we take every surname meaning at its face value, than the Van Polen clan ought to look for their origin somewhere in Poland. Since many Central and Eastern Europeans gravitated westwards over the centuries this sounds all very plausible.
Before we consider this idea, there are some Dutch roots’ alternatives to explore.
Near the northern Dutch town of Delfzijl there is a tiny hamlet Polen. Was it perhaps an outpost of Polish nobility?
Archives of the central Dutch municipality of Putten show that it had a farmstead called Polen. Its owner, Geurt Hendriksen settled on Van Polen as his surname in 1812.
Geurt Hendriksen was not the first Van Polen in the Netherlands, however. In the late 1700s, a certain Obe Jacobs of Bolsward was known as Pool, Pooltje and Van Polen. His offspring was named Van Polen.
Why would Dutch people call a neighbour Van Polen, after a foreign country?
In this case, I do not think they did. Far more likely they named both the hamlet and the farm after a topographical feature in the Dutch landscape, which lays at the root of a much wider range of surnames. That Obe Jacobs during his life was known by three closely related surnames, as identified above, should tell us something about naming in earlier times.
I will end this post with linguistic teasers: Is Polen the plural of the far more frequent singular Pol surname? Or should the plural of Pol be Pollen? This then begs the question: what is a Pool or a Pol?