Lieutenant field marshal, also frequently historically field marshal lieutenant (German: "Feldmarschall-Leutnant" , formerly "Feldmarschallleutnant", historically also "Feldmarschall-Lieutenant" and, in official Imperial and Royal Austrian army documents from 1867 always "Feldmarschalleutnant", abbreviated "FML"), was a senior army rank in certain European armies of the 17th to 20th centuries.
 It emerged as the rank of field marshal (German: "Feldmarschall" ) came to be used for the highest army commander in the 17th century (having originally been the equivalent of a cavalry colonel).
 In German-speaking countries the commander-in-chief usually appointed an "under marshal" ("Untermarschall") or "lieutenant field marshal" to support and represent the field marshal.
 Amongst his functions as the personal deputy to the field marshal, were the supervision of supply depots and routes, and inspection of the guards.
Field marshal (or field marshal, abbreviated as FM) ( , ) is a five–star general officer rank and the highest attainable rank in the Indian Army.
 Field marshal is ranked immediately above general, but not exercised in the regular army structure.
 It is a largely ceremonial or wartime rank, having been awarded only twice.
 A field marshal's insignia consists of the national emblem over a crossed baton and sabre in a lotus blossom wreath.
The 1940 Field Marshal Ceremony refers to a promotion ceremony held at the Kroll Opera House in Berlin in which Adolf Hitler promoted twelve generals to the rank of "Generalfeldmarschall" ("field marshal") on 19 July 1940.
 It was the first occasion in World War II that Hitler appointed field marshals due to military achievements.
Field Marshal Kodandera "Kipper" Madappa Cariappa, OBE (28 January 1899 – 15 May 1993) was the first Indian commander-in-chief (C-in-C) of the Indian Army.
 He led Indian forces on the Western Front during the Indo-Pakistani War of 1947.
 He is one of only two Indian Army officers to hold the five-star rank of field marshal; the other being Field Marshal Sam Manekshaw.
 He was appointed commander-in-chief of the Indian Army in 1949.
Generaloberst, in English Colonel General, was, in Germany and Austria-Hungary—the German "Reichswehr" and "Wehrmacht", the Austro-Hungarian Common Army, and the East German National People's Army, as well as the respective police services—the second highest general officer rank, ranking above full general but below general field marshal.
 It was equivalent to "Generaladmiral" in the "Kriegsmarine" until 1945, or to Flottenadmiral in the "Volksmarine" until 1990.
 The rank was the highest ordinary military rank and the highest military rank awarded in peacetime; the higher rank of general field marshal was only awarded in wartime by the head of state.
 In general, a Generaloberst had the same privileges as a general field marshal.
Field Marshal Gardihewa Sarath Chandralal Fonseka, RWP, RSP, VSV, USP, MP, rcds, psc (Sarath Fonseka) (Sinhalese: ෆීල්ඩ් මාෂල් සරත් ෆොන්සේකා , Tamil: பீல்ட் மார்ஷல் சரத் பொன்சேகா , born 18 December 1950) is a Sri Lanka's highest rank soldier and politician who was the first Sri Lankan Army officer to be promoted to the rank of Field Marshal.
 He was the eighteenth Commander of Sri Lankan Army, and under his command the Sri Lankan Army ended the 26-year Sri Lankan Civil War in 2009, defeating the rebel Liberation Tigers of Tamil Eelam; he thereafter briefly served as the Chief of Defence Staff.
 After retiring from the Army with the rank of General, he entered politics as the common opposition candidate in the 2010 presidential election contesting against President Mahinda Rajapaksa.
 Following his controversial defeat in the presidential election he was elected to Parliament in the general election that followed.
 Soon after he was made a political prisoner and lost his parliamentary seat.
 Fonseka supported Maithripala Sirisena in the 2015 presidential election and following his victory, the newly appointed President Sirisena gave Fonseka a full pardon reinstating his civic rights, military rank and decorations.
 Later he was promoted to the newly created rank of Field Marshal on 22 March 2015.
 On 9 February 2016 he was appointed to Parliament, and he was appointed Cabinet Minister for Regional Development on 25 February 2016.
The Hossbach Memorandum was the summary of a meeting on 5 November 1937 between German dictator Adolf Hitler and his military and foreign policy leadership where Hitler's future expansionist policies were outlined.
 The meeting marked a turning point in Hitler's foreign policies, which then began to radicalize.
 According to the Memorandum, Hitler did not want war in 1939 with Britain and France.
 What he wanted was small wars of plunder to help support Germany's struggling economy.
 The memorandum was named for the keeper of the minutes of the meeting, Hitler's military adjutant, Colonel Count Friedrich Hossbach.
 Besides Colonel Hossbach and Hitler, those attending the meeting were: the Reich Foreign Minister, Baron Konstantin von Neurath; the Reich War Minister, Field Marshal Werner von Blomberg; the Army Commander, General Werner von Fritsch; the Kriegsmarine Commander, Admiral Erich Raeder; and the Luftwaffe Commander, Hermann Göring.
Wilhelm Keitel (22 September 1882 – 16 October 1946) was a German field marshal who served as Chief of the Armed Forces High Command ("Oberkommando der Wehrmacht" or OKW) in Nazi Germany during World War II.
 According to David Stahel, Keitel was "well known and [...] reviled as Hitler's dependable mouthpiece and habitual yes-man" among his military colleagues.
Ernst John von Freyend (25 March 1909– 24 March 1980) was a German Oberkommando der Wehrmacht officer who served during World War II as the adjutant to Field Marshal Wilhelm Keitel.
 He is notable for unwittingly helping to place the 20 July plot bomb that was intended to kill Adolf Hitler.
Wilhelm Emanuel Burgdorf (15 February 1895 – 2 May 1945) was a German general in the Wehrmacht during World War II, who served as a commander and staff officer in the German Army (Wehrmacht) (army).
 In October 1944, Burgdorf assumed the role of the Chief of the Army Personnel Office ("Heerespersonalamt") and Chief Adjutant to Adolf Hitler.
 In this capacity, he played a role in the forced suicide of Field Marshal Erwin Rommel.
 Burgdorf committed suicide in the "Führerbunker" on 2 May 1945 at the conclusion of the Battle of Berlin.

Question: Who served as adjutant to the field marshal known as Hitler's mouthpiece?
Answer: Ernst John von Freyend