How important was religion in the development of the Dutch Revolt?

A-Level: History

...
The outbreak of the first revolt in 1566 was catalysed by the adoption of a harsh religious policy in the Netherlands by Philip which served to widen the divide between himself and the Dutch grandees. By the time of Philip’s accession to the Imperial throne, the Netherlands had witnessed a steady growth of Calvinism, most especially in the Southern provinces where there had been an influx of Huguenot refugees from France. Provincial Dutch magistrates who were traditionally tolerant of heterodoxy and processed the right to preside over heresy cases were threatened by the introduction of Spanish inquisitors as tools to renounce heresy and were riled into defending their local privileges. While these Grandees and magistrates were far from enthusiastic Calvinists, they would not bow to reductions in their political power and were reluctant to be dictated to by Spanish authorities. This is clearly highlighted in Egmont’s journey to Spain in 1565, whereby he spoke on behalf of all Grandees requesting that Philip relax heresy laws and recognise the authority of the Council of State. However Philip’s response in the form of the letters from the Segovia Woods demonstrated his hardline religious policy and the fact that he would be making no concessions to the Calvinists. The issue of the Heresy Laws would therefore prove to initiate the first revolt, with regent Margaret of Parma being forced to moderate the Heresy Laws after pressure from 400 armed members of the lesser nobility. This leniency increased Calvinist confidence and strength and acted as the ultimate trigger for the revolt and the events surrounding the iconoclastic fury of 1566.
...

*Very simple registration required first