South England Flood of February 1287

We've been looking lately at catastrophic floods of the Middle Ages, like those that took place on the feast days of St. Marcellus and St. Lucia. These floods not only caused great destruction and loss of life, in some cases they also made topographical/geographical changes that persisted into the future.

St. Lucia's Flood in December 1287, along with an event called the South England Flood of February 1287, radically changed the coastline of part of England.

The map shows dotted lines where the current coastline lies, and how previously there were towns linked to the sea that are now far inland. Unlike in the Netherlands where water forced its way inland and created new coastal towns that were formerly landlocked, the storm surge in February 1287 not only did this in some cases but also caused collapsing cliffs and silting that blocked formerly coastal towns from the sea. A cliff at Hastings collapsed, taking part of Hastings Castle with it and blocking the harbor at Hastings from future trade.

Another town, New Romney, used the River Rother as its trade link to the sea. The storm diverted the river, leaving New Romney a mile away from the water. The river's course ran to Rye, increasing its value as a trading port.

Further north along the coast was the town of Dunwich, an important seaport on the North Sea. A storm surge in 1286, followed by the South England Flood and St. Lucia's, so hammered the East Anglian coast that it declined economically as well as geographically. At its peak it was similar in size to London in the 1300s; the census of 2001 put its population at 84.

The flood of 1287 changed the makeup of the Cinque Ports, a designation that has been technically wrong for a very long time. Next time we'll discuss what the Cinque Ports are, and if there really are cinque.

St. Lucia's Flood

St. Lucia's Day, commemorating a 4th century martyr, is 13 December. On that date in 1287, one of the largest floods in recorded history took place in the North Sea. A similar flood in 1953 allows us to look back and ascribe the 1287 event to a particularly high tide and a particularly low pressure system. The North Sea rose enough to pour over dikes and seawalls, flooding the Netherlands and North Germany. Estimates put the death rate at 50,000 in Germany alone, 80,000 people in total.

The flood also made permanent changes to the countryside. The term "Zuider Zee" (Frisian "Southern Sea") begins to be used at this time for the body of water that was created by this flood. The Zuider Zee was expanded by the flood on St. Marcellus day in 1362. The area called the Zuider Zee was already a body of water: the freshwater Lake Flevo (also called Almere). The Flood connected it to the North Sea through a flooded forest and turned it into the saltwater Zuider.

Economic and political changes followed the geographical upheaval. The West Frisian city of Stavoren (officially the oldest city in Friesland, having been granted a charter in the 1060s) was a trade center on the bank of a river (the Vlie). The flood built up a sand bank that interfered with its shipping and started its decline. The Zuider also brought the coastline to other cities that promptly took advantage of it. The formerly landlocked city of Harlingen became a new seaport. The province of West Frisia became separated from the rest of Friesland by a strait that was nine miles wide at its narrowest; it was annexed by the County of Holland (a state of the Holy Roman Empire).

The same storm affected England, where the water rose several feet in Norfolk. It was a year of storms and flooding in England. Several months earlier England experienced the South England Flood of 1287. It likewise caused economic changes, as it crippled one of England's chief seaports, Dunwich. Tomorrow we'll see what happened then and there.

Saint Marcellus's Flood

A year ago, in May 2023, a survey in the Wadden Sea off North Frisia discovered the remains of the sunken church of Rungholt. The town of Rungholt had a population of about 3000 people. It was one of numerous places destroyed on the night of 15 January 1362, during an event called the Grote Mandrenke (Low Saxon: "Great Drowning of Men").

Also known as St. Marcellus's Flood (because the storm surge peaked on the 16th, which was the feast day of St. Marcellus), it was the result of a new moon with high tides and an extratropical cyclone.

A storm surge/tide swept from the North Sea from England and the Netherlands to Denmark and Germany. It battered and eroded the coasts, changing coastlines. Islands were broken up, new islands were created by breaking up the mainland near the coasts, and whole coastal towns were destroyed. An estimated 25,000 people lost their lives in the flooding.

This event is also called the "First St. Marcellus's Flood" because, on the same date in 1219, a storm surge along the coasts of West Friesland and Groningen (most northeastern province of the Netherlands) killed 36,000 people.

The Zuider Zee (Dutch: "Southern Sea"), a shallow bay of the North Sea in the northwest Netherlands, is believed to have been expanded at this event. It had been called that before this time, however, because of an even greater flood, also named for a saint. Tomorrow I'll tell you about St. Lucia's Flood and the creation of the Zuider Zee.