I have seen a great deal of supposition regarding the possibility of the Dutch Roosas being of Spanish/Jewish origins. There seem to be two firmly rooted camps; those who unquestionably support the theory, and those who believe it to be only a "legend". Hard evidence to support either argument has yet to surface.
Bert Feldman asserted that the Roosas were "from a rabbinical family", yet nobody has been able to identify his sources for this. His being Jewish himself does not qualify him for special knowledge that would enable him to ascertain this. Strictly speaking, Mr. Feldman was, at best, an amatuer historian making an educated guess. And, without his source material, we can only wonder at what information he used as a basis for his statement.
That being said, there is enough historical background material available to convince me that the assertions made by Abraham Guijsbert Roosa of the family being of Spanish origins may be true. (The Nederlandse Familienamen Databank of the Marteens Institute states that Roosa only claimed Catalon descent, nothing of Jewish origins). First and foremost, anyone bothering to look at old Dutch records will find that the name was spelled "Rosa" with one 'o'. In many instances, it is "de Rosa". Kingston Dutch Reformed Church records from the 1600's list it as "Rosa" with one O. Secondly, after culling through many available online records from the state archives of the Netherlands, I cannot find one reference to this name prior to the end of the 1400's. I did, however, find Jewish names; Coen and Haym.
Jews were in Gelderland from the middle of the 14th century, particularly in Nijmegen. The main migration of Sephardin came at the end of the 16th century following Dutch independence from Spain, but there had been Jewish communities in Holland for over two centuries already.
Many Jewish families from the Catalon region of Spain did migrate to Holland. And, the city of Rosas is in this part of Spain, a region heavily populated by Jews during the middle ages. Rosa/Rosas was a Jewish family in that region.
This is where the "theory" of Roosa Spanish roots do look more than merely plausible. The coat of arms for the Roosa family (Dutch) is three stemed roses (two over one)on a field of gold. The coat of arms for the city of Rosas Spain is three roses (two over one).
In Spanish heraldry roses were rendered more realistically
than the familiar English rose, and they were shown with stems. Additionally, Spanish heraldry followed the custom of the French in presenting trinaries (groups of objects in threes). Many Sephardic Jew coats of arms followed this same rule of trinaries, particularly in using a set of 3. One can find many examples with 3 Stars of David, 3 hats, 3 trees, and so on. And, these families continued their coats of arms even after emigrating to Holland. At least one known Sephardic coat of arms for a family by the name of Rosa is a realistically rendered stemed rose on a field of gold.
The name Heyman has two historic origins. It is a variation of "Herman", like Herman Munster (I have actually run across this name in historical sources). However, the interesting take on this name is that it is also an anglicized corruption of "Heym" or "Haym", itself an anglicization of "Chaim". Chaim is the Hebrew word for "life", and is a Hebrew name. I have encountered the name "Heym" in early 15th century tax lists alongside names like "Coen", another Hebrew name. So, it is likely that there were Dutch Jews named "Haym" who eventually became known as "Heyman".
I am not saying that either argument, the one for or against, the Roosa family being Spanish Jews lacks merit. However, while finding information that is consistent with the claim of Sephardic origins, I've found nothing refuting the idea. Taking into consideration all of this information when exmaining Abraham's claim, one can see that the story of the Roosa family's Spanish origins is not inconsistent with facts. It is even consistent with the possibility of their roots being Jewish in origin, as well as Spanish. This does nothing to prove the claim, but it does place it within a context that forces us to give the idea more serious thought.