William now found himself faced with something like financial ruin.  Mercenary armies are very costly, and by bitter experience he had learnt the futility of opposing a half-hearted and badly disciplined force to the veteran troops of Alva.  He resolved therefore to go in person to Holland to organise and direct the strong movement of revolt, which had found expression in the meeting of the Estates at Dordrecht.  His agents had long been busy going about from town to town collecting funds in the name of the prince and encouraging the people in their resistance to the Inquisition and to foreign tyranny.  William’s declaration that henceforth he intended to live and die in their midst and to devote himself with all his powers to the defence of the rights and liberties of the land met with willing and vigorous support throughout the greater part of Holland, West Friesland and Zeeland; and contributions for the supply of the necessary ways and means began to flow in.  It was, however, a desperate struggle to which he had pledged himself, and to which he was to consecrate without flinching the rest of his life.  If, however, the prince’s resolve was firm, no less so was that of Alva.

Alva had his enemies at the Spanish court, always ready to excite distrust against the duke in the mind of the suspicious king.  In July, 1572, the Duke of Medina-Coeli had been sent from Spain to enquire into the state of affairs in the Netherlands; probably it was intended that he should take over the administration and supersede the governor-general.  On his arrival, however, Medina-Coeli quickly saw that the difficulties of the situation required a stronger hand than his, and he did not attempt to interfere with Alva’s continued exercise of supreme authority.  The governor-general, on his side, knew well what was the meaning of this mission of Medina-Coeli, and no sooner was the army of Orange dispersed than he determined, while the reins of power were still in his hands, to visit the rebellious towns of the north with condign vengeance.

At the head of a powerful force, Frederick of Toledo marched northwards.  Mechlin, which had received Orange, was given over for three days to pillage and outrage.  Then Zutphen was taken and sacked.  Naarden, which had, though without regular defences, dared to resist the Spaniards, was utterly destroyed and the entire population massacred.  Amsterdam, one of the few towns of Holland which had remained loyal to the king, served as a basis for further operations.  Although it was already December and the season was unfavourable, Toledo now determined to lay siege to the important town of Haarlem.  Haarlem was difficult of approach.  It was protected on two sides by broad sheets of shallow water, the Haarlem lake and the estuary of the Y, divided from one another by a narrow neck of land.  On another side was a thick wood.  It was garrisoned by 4000 men, stern Calvinists, under the resolute leadership of Ripperda and Lancelot