 With the title of "wirklicher geheimer Rat", he was sent to Naples in 1852 as an envoy.Shortly before the outbreak of the Crimean War in 1854, he was sent as head of the Prussian embassy in London, and was successful in promoting good Anglo-Prussian relations.In October 1861, Bernstorff left London to become the Prussian Foreign Minister under the Prime Minister Charles Anthony, Prince of Hohenzollern.