A thesis submitted for the degree of Doctor of Philosophy of the University of Luton. ; During the Great War many European armies (most notably the Russian) collapsed due to major disciplinary problems. However, the British Expeditionary Force avoided these problems up until the Armistice of November 1918. This thesis examines how the discipline and morale of the RE.F. survived the war, by using a case-study of the Irish regiments. In 1914 with Ireland on the brink of a civil war, serious questions had been raised relating to the loyalty of the Irish regiments, particularly in the aftermath of the Curragh Incident. Indeed, intelligence reports prepared for Irish Command suggested that some reserve units would defect en masse to the U.V.F. if hostilities broke out in Ireland. As the Great War progressed, the rise of Sinn Fein produced further concern about the loyalty of Irish troops, seen most vividly in the decisions not to reform the 16th. (Irish) Division following the German Spring Offensive of 1918 and to remove Irish reserve units from Ireland in 1917-18. Nevertheless, a detailed study of courts martial (studied comprehensively in a database project) recently released by the P.R.O., demonstrates that many of the fears relating to Irish troops were groundless. Certainly Irish courts martial rates tended to be high, however, these figures were inflated by cases of drunkenness and absence, not disobedience. Likewise, while a number of mutinies did occur in Irish regiments during the war, this study has revealed that mutinies were much more common in the B.E.F. as a whole, than has been previously believed. This study has also considered the discipline and morale problems caused by the rapid expansion of the British army in 1914 and the appointment of many officers, especially in the 36th. (Ulster) Division, on the basis of their political allegiances rather than professional knowledge. Nevertheless, in general it appears that the discipline and morale of the Irish units in the B.E.F. was very good. Incidents ...