The purpose of this study is to examine the program for training of America's first division in Europe in 1917, from the date of its activation until it was certified ready for combat as a division in January, 1918. Thus the training program of the 1st Division is explored chronologically through three phases: basic individual training as conducted by the division, the centralization and promulgation of training doctrine and training policies by Headquarters, American Expeditionary Forces, and the final phase of the training program during which the division was judged prepared to enter combat. The primary sources used for this study were drawn from a compilation of letters, training programs, and memoranda of the A.E.F., 1st Division, and French Army, gathered into several volumes by the War College and entitled World War Records, First Division, A.E.F. Memoirs and biographies of some of the principles involved in this effort were also used. Conclusions of the thesis are that American training doctrine and principles for the 1st Division was evolutionary in nature and emerged as members of the A.E.F. gained experience. The 1st Division was trained in a very systematic manner from the simplest to the most difficult of tasks, and was successfully prepared for its entry into combat.