Leslie Kerswill, who has died aged 99, was taken prisoner in 1940 near Dunkirk and, having escaped, travelled hundreds of miles on foot in the depths of winter from Poland to the Allied lines. In January 1940, Kerswill embarked with 4th Bn Royal Berkshire Regiment bound for Cherbourg, as part of the British Expeditionary Force. On the River Dendre, east …