 Complete the following phrase:  Manstein entered the 3rd Infantry Regiment in 1822. In 1841 he was promoted to first lieutet and he became an adjutant on the staff of the I Army Corps. By 1864 he had been promoted to the rank of Major General  and given command of the 6th Infantry Division, which he led during the Second Schleswig War in the Battle of Dybbøl and at 