Originally conceived by Lt. Col. Ernest Swinton in 1914 and developed under the encouragement of Winston Churchill, the first tank, the Mark I, debuted at the Battle of the Somme on September 15, 1916. Although the commanding officer was criticized for spreading the tanks out along the front line instead of using them in a tight formation, the British did move their front line forward about 2,500 yards on that first day. They did not, however, break through the German line as they had hoped.