Prior to the Grote Mandrenke flood in 1362 , the area comprising the present-day island was a part of the former island of Strand in Edoms Hundred . As a result of the flood , which laid waste to much of Strand and submerged the city of Rungholt , three small islands were removed from the area of Strand : Südfall , Nübell ( or " Nubel " ) and Nielandt . Over time , Südfall and Nübell were gradually eroded into the sea , and their inhabitants resettled on Nielandt , renaming it Südfall . In the catastrophic Burchardi flood of 1634 , Strand was torn asunder by the sea and its largest settlements were destroyed , causing a great loss of life and property . Nearby Südfall , however , weathered the disaster . Its inhabitants made a living primarily by way of agriculture and fishing , supplemented by occasional beachcombing . The twelve families who lived on the island perished in the Great Hallig Flood on 3 – 4 February 1825 . The three warfts on the western side of the island were totally submerged , and the total area of the island was halved . The single warft that remains on the island today was constructed in 1828 . Ownership of the island has changed hands numerous times since then
Burchardi flood
Burchardi flood
Südfall