West Frisia (historical)

West Friesland (also West Frisia; West-Frisian: West-Fryslân) is a contemporary region in the Northwest of the Netherlands, in the province of North Holland.

The River Vlie (also called Fli), is an extension of the IJssel branch of the Rhine River. The river divides the northern Netherlands into two parts, the western and the eastern part. In the eleventh century, heavy rainfall caused the river to flood over large parts of the land. The Zuiderzee bay (previously a lake) was formed, separating West Friesland from the contemporary Province of Friesland. In the Middle Ages, the Westflinge area of West Friesland became an island, bordered on the north by the Medem and Zijpe inlets, and to the south by various interconnecting lakes (now polder land) that were connected with the Zuiderzee. Because of this, the toponym "West Friesland" was applied more to the Westflinge area than to the original West Friesland.

For approximately 300 years, West Friesland operated as an autonomous area as the West Frisians did not wish to be vassals of lords from Holland. Floris V, Count of Holland, attempted to unite Holland and West Friesland during his reign and he succeeded in annexing West Frisia. It was his successor, John I, who achieved ultimate victory over the West Frisians in 1297. West Friesland formed a united province with Holland in the Dutch Republic, though it was recognized an autonomous region, and the parliament of said province, commonly known as Holland, was formally known as the States of Holland and West Friesland. During the time of the United Provinces, West Friesland had its own independent Admiralty of the Northern Quarter. Any admiral serving within this admiralty or the two other Hollandic admiralties (Amsterdam and the Admiralty of de Maze) had the title of Admiral of Holland and West Frisia.

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