For a time the common hatred of all the people for the foreigner welded them into a united whole; but no sooner was the pressure of the Spanish yoke even slightly relaxed than the mutual antipathy of Calvinist and Catholic showed itself.

If we look closely into the causes why the North should become predominantly Protestant while the South gradually reverted to an entirely Catholic faith, we must see that the reasons were in part racial, in part geographical and in part social.

Geographically and linguistically the Northern provinces looked for their culture to Germany, and the Southern provinces to France.

Moreover the easy defensibility of Holland and Zeeland, behind their moats, made them the natural refuge of a hunted sect and, this tendency once having asserted itself, the polarization of the Netherlands naturally followed, Protestants being drawn and driven to their friends in the North and Catholics similarly finding it necessary or advisable to settle in the South.

Moreover in the Southern provinces the two privileged classes, clergy and nobility, were relatively stronger than in the almost entirely bourgeois and commercial North.