For the English cricketer, see Frederic Walker.Captain Frederic John Walker CB, DSO & Three Bars (3 June 1896 – 9 July 1944) (his first name is given as Frederick in the Oxford Dictionary of National Biography and some London Gazette entries) was a Royal Navy officer noted for his exploits during World War II. Walker was the most successful anti-submarine warfare commander during the Battle of the Atlantic and was known more popularly as Johnnie Walker (after the whisky).