in the so-called Siebenhardenbeliebung (the compact of the seven hundreds) in 1424. North Frisia as a region was first recorded in 1424 although Saxo Grammaticus had written about Frisia minor [Lesser Frisia], a region in Jutland, already in 1180. Modern era Several floods such as the Grote Mandrenke in 1362 and the Burchardi Flood of 1634 damaged great parts of the North Frisian coastal area. In these floods entire islands were destroyed and a great part of North Frisian language was torn apart in linguistical and political terms. Additional hardship was brought about by a number of wars, such as the Thirty Years War that reached North Frisia in 1627, the Second Northern War between Sweden and Denmark 1657–1660, and the Great Northern War from 1700–1721 where Tönning was besieged and partially destroyed in 1713. With the onset of whaling in the 17th and 18th century, the people from the North Frisian Islands soon developed a reputation of being very skilled mariners, and most Dutch and English whaling ships bound for Greenland and Svalbard would have a crew of North Frisian islanders. Around the year 1700, Föhr had a total population of roughly 6,000 people, 1,600 of whom were whalers. At the height of Dutch whaling in the year 1762, 1,186 seamen from Föhr were serving on Dutch whaling vessels alone and 25% of all shipmasters on Dutch whaling vessels were people from Föhr. Another example is the London-based South Sea Company whose commanding officers and harpooners were exclusively from Föhr. In the early 18th century, Sylt island was home to 20 captains who took part in the Greenland whaling. Until 1864, North Frisia was a part of the Danish Duchy of Schleswig (South Jutland) but was transferred to Prussia after the Second Schleswig War. During this time of German-Danish conflicts, a North Frisian identity was propagated by people such as Christian Feddersen (1786-1874) who simultaneously denounced nationalist tendencies. The North Frisian coat of arms has been attributed to him. While not designed according to heraldic rules, the shield contains a Frisian eagle on the right side and on the left there is a golden crown in blue above a black kettle in a red field. The eagle has been interpreted as a symbol of the Frisian freedom granted by the Holy Roman emperor, the crown represents the Danish kings who ruled the area until the mid 19th century. The