After his abdication the two great monarchies of Austria and Spain were separated; but though ruled by different persons, they were still in the same family, and tended toward that unity of aim and sympathy which marked dynastic connections in that and the following century.

To this bond of union was added that of a common religion.

During the century before the Peace of Westphalia, the extension of family power, and the extension of the religion professed, were the two strongest motives of political action.

This was the period of the great religious wars which arrayed nation against nation, principality against principality, and often, in the same nation, faction against faction.

Religious persecution caused the revolt of the Protestant Dutch Provinces against Spain, which issued, after eighty years of more or less constant war, in the recognition of their independence.