British army officers wrongly believed WW1 troops fought better if they were drunk in battle, an addiction specialist has claimed.

Senior commanders encouraged drinking among soldiers as they were following medical advice that claimed alcohol made them more effective fighters.

Health experts believed that rum would “warm and dry out chilled troops” who were suffering from dysentery caught in the trenches, according to Dr Tim Leighton, Director of Professional Education and Research at Action on Addiction.

But troops were unhappy with their “rum rations” of 1/16th pint per day and wanted the “more generous” levels given to soldiers who fought in the army from the early 18th century.

Many colonels agreed that the recommended level was too low and would give nervous fighters extra helpings to improve their confidence before infiltrating enemy lines.

Lt Colonel J.S.Y. Rogers, a medical officer to the 4th Black Watch, said in the Report of Enquiry into Shell Shock in 1922: “Had it not been for the rum ration I do not think we should have won the war. Before the men went over the top they had a good meal and a double ration of rum and coffee.”