Admiral of the Narrow Seas

The Admiral of the Narrow Seas also known as the Admiral for the guard of the Narrow Seas was a senior Royal Navy appointment. The post holder was chiefly responsible for the command of the English navy's Narrow Seas Squadron also known as the Eastern Squadron that operated in the two seas which lay between England and Kingdom of France (the English Channel particularly the Straits of Dover) and England and the Spanish Netherlands later the Dutch Republic (the southern North Sea) from 1412 to 1688. His subordinate units, establishments, and staff were sometimes informally known as the Command of the Narrow Seas.
History.
The first royal commission as Admiral to a naval officer was granted in 1303. By 1344 it was only used as a rank at sea for a captain in charge of a fleet or fleets. 
In the fifteenth, sixteenth and seventeenth centuries, the Kingdom of England claimed sovereignty over certain bodies of water close to the British Isles: those between the Kingdom of France and England (the English Channel particularly the Straits of Dover) and the Spanish Netherlands later the Dutch Republic and England (the southern North Sea). As a result of England's claim of these territorial waters there was an enforceable requirement placed on any foreign ships passing through the area to acknowledge all English warships. England also exercised control over all fishing rights within the same waters. 
Among the most important naval postings during these times was the "Admiral of the Narrow Seas", sometimes called the "Vice-Admiral of the Narrow Seas" to denote that he was junior to the Lord Admiral of England. These flag officers were formally appointed by the crown. His responsibilities were to guard the narrow seas from foreign threats, protect English fishing vessels and enforce English sovereignty over said waters. 
Claims to the narrow seas lasted until the United Kingdom of Great Britain and Ireland, along with other European countries, agreed to set a new three-mile limit in 1822.
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