Admiralty in the 16th century has organized the fleet into squadrons from at early 13th century and certainly during the 16th century. In 1560 three squadrons were operating in the Channel, Irish Sea and North Sea Until the 16th century, admirals were high officials under kings, and were charged with protecting the realm from sea attack. The English navy's Narrow Seas Squadron also called as the Eastern Squadron mainly operated in the two seas which laying 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). Include:
St. Brice's Day massacre there was significant loss of life, though evidence is lacking on any specific estimates. Among those thought to have been killed is Gunhilde, who may have been the sister of King Sweyn I of Denmark. Her husband Pallig Tokesen, the Danish Ealdorman of Devonshire, may also have died in the massacre or, according to a different version, played a part in provoking it by his defection to join raiders ravaging the south coast. The massacre in Oxford was justified by Æthelred in a royal charter of 1004 explaining the need to rebuild St Frideswide's Church (now Christ Church Cathedral): The