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.