Volume three of this authoritative Churchill biography chronicles his years of triumphant leadership in the Admiralty during World War I.   Acclaimed British historian Sir Martin Gilbert continues the official biography of Sir Winston S. Churchill the eventful period between 1914 and 1916, with a full account of his achievements as first lord of the Admiralty during the Great War. These include Churchill’s efforts to prolong the siege of Antwerp, his support for the use of air power, and his part in the early development of the tank. It shows the forcefulness with which he argued for an offensive naval policy, first against Germany, then against Turkey.   Gilbert examines the political crisis of May 1915, during which the Conservative Party forced Asquith to form a coalition government. The Conservatives insisted that Churchill leave the center of war policymaking for a position of increasing political isolation. In the next seven months, while the Gallipoli campaign was being fought, Churchill served as chancellor of the Duchy of Lancaster, with no authority over military or naval policy.   Resigning from the cabinet in November 1915, Churchill was appointed lieutenant-colonel, commanding an infantry battalion in the trenches of the Western Front. In May 1916, he returned from the trenches, hoping to reenter political life, but his repeated attempts to regain his once-substantial influence were unsuccessful.   “A milestone, a monument, a magisterial achievement . . . rightly regarded as the most comprehensive life ever written of any age.” —Andrew Roberts, historian and author of The Storm of War   “The most scholarly study of Churchill in war and peace ever written.” —Herbert Mitgang, The New York Times