The proposition that “whiteness” dates to the 17th century seems reasonable, but it’s not that before then ethnic distinctions weren’t made, but rather that they were made in religious rather than biological terms. Between the turn-of-the-millennia Christianization of Northern and Eastern Europe and the overseas missionary work of the European Age of Exploration, Christendom had, with the noble (but quite peripheral) exception of Ethiopia, basically the same borders that would later be rendered as whiteness

The parallels hold pretty well even for distinctions within Christendom/whiteness - Protestant/Catholic/Orthodox maps imperfectly but sufficiently to Nordic/Mediterranean/Alpine.

The Spanish Inquisition against mariscos and marranos is passed down to us as a confessional conflict, Catholics against (suspected) crypto-heathens, but a modern Northern Italian/Iberian effort to subjugate and drive off people of Moorish and Jewish heritage would be read as racial conflict.