 The crossing between Gravesend and Tilbury was also of considerable importance, which had prompted the Tudors to build fortifications on both sides of the river at that point.The impetus for the construction of New Tavern Fort came from the threat posed by the United Kingdom's adversaries in the American War of Independence - the newly created United States of America and its European allies, France and Spain.Serious weaknesses in British coastal defences had been revealed in 1778 by the American adventurer John Paul Jones in his raid on Whitehaven, Cumbria.