In 1566, Margaret of Parma, regent of this part of Northern Europe in the name of the King of Spain, receives a delegation of Catholic and Protestant noblemen.

They ask for freedom of religion, amongst other things. Spain refuses to grant them this. Spain succeeds in regaining control of the Southern Netherlands, but the Northern Netherlands remains de facto independent. Many Protestant southerners flee to the North, thus contributing to Amsterdam’s Golden Age.

The border that was established in 1588 still largely corresponds to the Belgian-Dutch border.