A mistake in the presentation: Ewan has been very much in use in Brittany (not only in Scotland), in different versions (Ewen, Iwan, Erwan), for a very long time.
Actually, Ewan is also a Breton name with different spellings (Ewan, Iwan, Ewen, Youenn, Erwan). Your presentation of the name is not totally correct as it is not only Scottish but also Breton; sorry.