From March 1941 Barber returned to the General Staff as a GSO1, until taking command, in October, of the 46th (Highland) Infantry Brigade, leading it through the Battle of Normandy in the summer of 1944. From 3 August 1944 Barber, when he was promoted to acting major-general, he commanded the 15th (Scottish) Infantry Division for the remainder of the campaign in north-west Europe. In this campaign, the 15th Division had the distinction to lead the three great river crossings of the Seine, the Rhine and the Elbe and Barber was awarded the bar to his DSO.