Leiden joined the Dutch revolt against the Spanish crown in 1572. A Spanish army first besieged the city in October 1573, and by the summer of 1574 nothing could get in. Museum De Lakenhal, the city's own museum, describes a town that ran out of food long before help came.
William of Orange, who led the revolt, could not break through on land. EARTH Magazine notes that his army was less than half the size of the king's. What the rebels did have were the Sea Beggars, sailors with small, flat boats. So on 3 August 1574 they cut the dikes along the Maas near Rotterdam and let the North Sea onto the farmland, hoping to sail to Leiden over the fields.
For weeks it did not work. The water did not rise nearly high enough to drive the Spanish away or to carry the boats to the walls. Then on 1 October heavy rain fell and strong winds drove seawater overland through the broken dikes. On the night of 2 October the Spanish forces withdrew in such a hurry that they left supplies behind.
The Sea Beggars reached Leiden on the morning of 3 October. An account quoted by EARTH says the townspeople were so weakened that scarcely anyone could stand. The rescuers handed out herring and white bread. Museum De Lakenhal tells of a kettle found in the abandoned Spanish camp near the Lammenschans fort; tradition says it held hutspot, a mash of carrots, onions and meat.
Four months later, on 8 February 1575, William of Orange founded Leiden University, the first in the Netherlands. The university itself says the gift is said to honour the city's resistance, and a popular legend adds that the citizens chose it over lower taxes. The war went on until 1648. Every 3 October Leiden still celebrates the rescue with herring, white bread and hutspot, a feast run by the 3 October Society since 1886.
