Mayr was the son of a magistrate. After graduating from high school, he was enrolled on 14 July 1901 in the 1st Bavarian Infantry Regiment in Munich as a cadet. Well regarded by his superiors, he made rapid progress, becoming
Leutnant in 1903 and
Oberleutnant in 1911. From August 1914 Mayr was with the 1st Bayerischen
Jägerbattailon. During the
First World War he was in combat in Lorraine and Flanders and involved in early 1915 with the German Alpine Corps. On 1 June 1915 Mayr was promoted to
Hauptmann (captain). In 1917, he was named on the General Staff of the Alpine Corps. On 13 March 1918 he was appointed commander of the 1st Bavarian
Jägerbattailon, with whom he served in the Eastern Army Group in Turkey from 20 July to 15 October 1918. Shortly after the war, from 1 December 1918, Mayr acted as company commander in the 1st Bavarian Infantry Regiment in Munich. On 15 February 1919 he was on leave from the military, but returned in May as commander of the 6th Battalion of the guards regiment in Munich and from 30 May as head of the "Education and Propaganda Department" of the General Command von Oven and the Group Command No. 4 (Department Ib) under Lieutenant-General von Möhl. In his capacity as head of the intelligence department, Mayr recruited Adolf Hitler as an undercover agent in early June 1919. Hitler's role involved informing on soldiers suspected of
communist sympathies. Hitler took part in "national thinking" courses at the Reichswehrlager Lechfeld near Augsburg which were organized by the Bavarian
Reichswehr under Captain Mayr. Mayr believed demoralized and Bolshevized forces should be taught national sentiments. After this training Mayr issued Hitler the order to become "
anti-Bolshevik educational speaker" to the soldiers at the Munich barracks. Furthermore, Hitler was sent as an observer to the numerous meetings of the various newly formed political parties in Munich. Hitler spent much time at the meetings and wrote reports on the political ideas, goals and methods of the groups. This included studying the activities of the DAP (German Workers' Party). Hitler became impressed with founder
Anton Drexler's
antisemitic, nationalist,
anti-capitalist and
anti-Marxist ideas. Drexler was impressed with Hitler's oratory skills and invited him to join the DAP, which Hitler accepted on 12 September 1919. After attending a further meeting on 3 October, Hitler stated to Mayr in his report "must join this club or party, as these were the thoughts of the soldiers from the front-line". Historian
Thomas Weber described the obscurity and secrecy behind the relationship between Hitler and Karl Mayr during the years of 1919 and 1920:Piece by piece, the picture that has conclusively emerged by putting all the surviving pieces of evidence together is the image of a Private Hitler who was shunned by most of the front-line soldiers as a 'rear area pig', and who was still unsure of his political ideology at the end of the war in 1918. The view of the
List Regiment as a band of brothers, with Hitler a hero at its heart, has its origins in Nazi propaganda, not in reality. The
First World War did not 'make'
Hitler. Even the revolutionary period seems to have had a far less immediate impact on Hitler's politicization than hitherto assumed. Central for Hitler's
radicalization was thus the post-revolutionary period, a time when he was still surrounded by people like
Ernst Schmidt and Karl Mayr, who like him possessed fluctuating political attitudes. This period in Hitler's life is still clouded in much secrecy.In March 1920, Mayr sent Hitler,
Dietrich Eckart and
Robert Ritter von Greim to Berlin to observe at close range the events of the
Kapp Putsch. On 8 July 1920, Mayr was released from military service as a major of the General Staff of the military district commands VII, but reappeared in September 1920 as commander of Section I b/P of army intelligence. Mayr in 1921 was a
Nazi Party supporter, but later became a critic. In 1925 he joined the
SPD. Subsequently, he was the leader and editor of the
Reichsbanner Schwarz-Rot-Gold, an SPD paramilitary force. In the early 1930s, Mayr collected among other things, information on Georg Bell, an associate of
Ernst Röhm, and other material against the Nazi Party, which he leaked in the Social Democratic press. After
Adolf Hitler's rise to power in 1933, Karl Mayr fled to
France. After the
German invasion of France in 1940, he was arrested in
Paris by the
Gestapo. Mayr was taken back to Germany and was incarcerated in
Sachsenhausen concentration camp until 1943, when he was transferred to
Buchenwald concentration camp and forced to work at the Gustloff ammunition plant, where on 9 February 1945 he was killed. == Notes and references ==