Most of the counties of Holland and Zeeland were occupied by rebels in 1572, who sought to end the harsh rule of the Spanish Duke of Alba, governor-general of the Netherlands.

The territory had a high density of cities, which were protected by defense works and by the low-lying boglands, which could easily be flooded by opening the dykes and letting in the sea.

In the meantime, due to his failure to quell the rebellion as quickly as he had intended, Alba submitted his resignation, which King Philip accepted in December.

[2][3] The leader of the Dutch rebels, William the Silent, Prince of Orange, attempted a relief of Leiden by sending an army into the Netherlands under the command of his brother, Louis of Nassau.

Valdez lifted the siege in April 1574 to face the invading rebel troops, but Sancho d'Avila reached them first and defeated them in the Battle of Mookerheyde, where Louis was killed.

Previously, the Prince's Admiral Louis de Boisot had assembled a fleet of more than two hundred small flat-bottomed vessels, manned by 2,500 veteran Dutch seamen, and carrying a large store of provisions for the starving townspeople of Leiden.

Instead, the rebel flotilla once again found their path blocked, this time by the Greenway dike, less than a mile inland of the Landscheiding, which was still a foot above the water level.

But Mayor van der Werff inspired his citizens to hold on, telling them they would have to kill him before the city could surrender, and that they could eat his arm if they were really that desperate.

In October, the Dutch patriots led by William the Silent destroyed the dykes in four locations in order to form an obstacle the Spanish troops could not overcome.

[5] A succession of fortified villages now stood in the way of the patriot fleet, and the Dutch Admiral was afraid even now of losing his prize, but the Spaniards, panicked by the rising waters, barely offered any resistance.

This was a formidable obstacle, but the Spaniards, adept at land fighting and not amphibious warfare, had despaired of maintaining so unequal a contest against the combined forces of the sea and the veteran Dutch seamen.

Accordingly, the Spanish commander Valdez ordered a retreat in the night of 2 October, and the army fled, rendered more fearful by a terrible crash they heard from the city, and assumed to be the men of Leiden breaking still another dam upon them.

In fact, part of the wall of Leiden, eroded by the sea water, had fallen, leaving the city completely vulnerable to attack, had any Spaniards chosen to remain.

According to legend, a little orphan boy named Cornelis Joppenszoon found a cooking pot full with hutspot that the Spaniards had had to leave behind when they left their camp, the Lammenschans, in a hurry to escape from the rising waters.

According to the ironical fiction still maintained by the Prince, that he was acting on behalf of his master Philip of Spain, against whom he was in fact in open rebellion, the university was endowed in the King's name.