Siege of Leiden (1574): The Dutch Flood Their Land to Win

The Siege of Leiden was a Spanish blockade of the Dutch city of Leiden in 1573–1574, during the Dutch Revolt against Philip II. After months of hunger and disease, the city was relieved on 3 October 1574 when the rebels flooded the surrounding countryside and sailed a fleet of flat-bottomed boats to its walls. The victory saved the heart of the rebellion in Holland and is still celebrated in Leiden every year.

Background

In 1572 the towns of Holland and Zeeland rose against Spanish rule and declared for William of Orange, as part of the wider Dutch Revolt. The Duke of Alba’s army struck back, sacking Naarden and capturing Haarlem in July 1573 after a long siege. Alkmaar, however, held out, and Leiden, one of the largest towns in Holland, became the next target.

Spanish forces under Francisco de Valdez first besieged Leiden from October 1573. That siege was lifted in March 1574 when the troops were called away to face an invasion by William’s brothers, Louis and Henry of Nassau, who were defeated and killed at Mookerheyde on 14 April 1574.

The second siege

The Spanish returned on 26 May 1574 and surrounded Leiden with a ring of more than 60 forts and earthworks. The city had not restocked its stores after the first siege, and food soon ran short. By late summer the inhabitants were eating horses, dogs and whatever they could find, and plague broke out.

Messages were carried in and out of the city by carrier pigeon and by messengers who slipped through the Spanish lines, keeping the defenders informed that help was being prepared. The Spanish repeatedly offered terms, including a pardon, and some citizens argued for surrender.

Leiden’s leaders, among them burgomaster Pieter Adriaansz. van der Werff, refused to surrender. A famous story says that van der Werff offered his own body to feed the hungry citizens rather than give in; it was told and retold in later centuries, but its details cannot be confirmed.

Breaking the dykes

William of Orange and the States of Holland decided on a desperate plan: to flood the land between the great rivers and Leiden. In early August 1574 the dykes along the Maas and the IJssel were cut, including near Rotterdam, and the sluices were opened. The plan meant ruining farmland that had taken generations to drain. Farmers protested, and the States of Holland had to promise compensation. The flooding was slow, because the water had to spread across many polders, each enclosed by its own dykes, which the rebels had to breach one by one.

A fleet of about 200 shallow boats, manned partly by Zeeland Sea Beggars and commanded by Admiral Louis de Boisot, was gathered to sail towards the city. For weeks the water was too shallow, and the fleet was stopped by further dykes and Spanish positions.

Relief

In late September and the first days of October storms and a change of wind drove the sea water inland and raised the level of the flood. The boats advanced, and the Spanish, threatened with being cut off by the rising water, abandoned their forts one after another.

During the night of 2–3 October the Spanish garrison left the Lammenschans, their strongest fort near the city. On 3 October 1574 Boisot’s fleet entered Leiden and distributed herring and white bread to the starving people. Soon afterwards the wind turned and drove the water back out to sea, which contemporaries saw as a sign of divine favour.

Consequences

The relief of Leiden prevented Spain from splitting Holland in two and showed that the rebels could defend their heartland by using water as a weapon. Spain’s war effort was also weakened by bankruptcy in 1575, which led to mutinies and the Spanish Fury at Antwerp in 1576.

On 8 February 1575 William of Orange founded Leiden University, the oldest university in the Netherlands, as a Protestant centre of learning for the rebel provinces. The popular tale that Leiden’s citizens were offered a choice between a reward of tax exemption and a university is a later legend.

Legacy

Every year on 3 October Leiden celebrates Leidens Ontzet (the Relief of Leiden) with parades, a fair and free herring and white bread. Many people also eat hutspot, a stew of mashed vegetables, recalling a pot said to have been found in the abandoned Spanish camp.

Timeline

• 1573, October: The first Spanish siege of Leiden begins.
• 1574, March: The first siege is lifted as troops leave to fight Louis of Nassau.
• 1574, 14 April: Louis and Henry of Nassau are killed at Mookerheyde.
• 1574, 26 May: The second siege begins.
• 1574, early August: The dykes along the Maas and IJssel are cut.
• 1574, 3 October: Boisot’s fleet relieves Leiden.
• 1575, 8 February: Leiden University is founded.

Why it matters

Leiden’s survival kept the rebellion in Holland alive at its most dangerous moment. It became a founding story of Dutch independence, linking the struggle against Spain with the Dutch mastery of water.