By 1945, his acts of resistance and sabotage against the Nazi regime came to light and Canaris was hanged in Flossenbürg concentration camp for high treason as the Allied forces advanced through Southern Germany.

[1] Canaris believed that his family was related to the 19th-century Greek admiral and politician Konstantinos Kanaris, a belief that influenced his decision to join the Imperial German Navy.

[5] By the outbreak of the First World War in 1914, Canaris was serving as a naval intelligence officer on board SMS Dresden, a light cruiser to which he had been assigned in December 1911.

[6] This was the only warship of Admiral Maximilian von Spee's East Asia Squadron that managed to evade the Royal Navy for a prolonged period during the Battle of the Falkland Islands in December 1914.

[12][13] Eventually, he was sent to Spain, where, in Madrid, his task was to provide clandestine reconnaissance over enemy shipping movements and to establish a supply service for U-boats serving in the Mediterranean.

[24] Canaris made some enemies within Germany during the course of his secret business and intelligence negotiations, partially as a consequence of the bankruptcy incurred by the film-maker Phoebus Film in his dealings with Lohmann (the 'Lohmann Affair').

[25] At some point in 1928, Canaris was removed from his intelligence post and began two years of conventional naval service aboard the pre-Dreadnought battleship Schlesien[21] and became captain of the vessel on 1 December 1932.

Two things stood out for Canaris about the Nazis; they represented a return to state-centered authoritarian government led by a charismatic leader, which he supported, and they were determined to throw off the shackles of the Treaty of Versailles.

[28] It is worth recalling that in the turmoil after the First World War in Germany, while the Weimar government was fledgling, Canaris helped establish home guard units in contravention of the treaty, sympathised with the Freikorps movement and participated in the Kapp Putsch.

[33] Then, in short order, Canaris caught wind of the dispute in the Reichswehr Ministry over the impending successor to the Abwehr chief Captain Conrad Patzig [de], who was forced to resign.

[34] His aspirations were quickly being realized, and in his zeal for his new job, Canaris paid "little heed" to the warnings from Patzig about the "fiendish" machinations of the party and its police organs.

[36] On 1 January 1935, a little less than two years after Hitler had taken control of the German government, Canaris was made head of the Abwehr, Germany's official military intelligence agency.

"[42] In May 1935, Canaris first donned the uniform of a rear admiral, a promotion that coincided with his responsibility for shielding Germany's burgeoning rearmament program from enemy counterintelligence agents, which meant a significant expansion of the Abwehr.

[43] The enlargement of the Abwehr mission brought Canaris into contact with "counterespionage virtuoso" Major Rudolf Bamler, who assisted him in establishing an extensive surveillance web over munitions factories, seaports, the armed forces and the media.

[48] Prompted by anti-Semitism, Canaris first suggested the use of the Star of David to identify Jews in 1935 to 1936, which was later used to set them apart from German citizens within the Reich, and eventually heralded their isolation, presaged their compulsory resettlement, and ultimately led to their physical annihilation.

[50] In fact, Germany provided aid to Franco's side, with Canaris using his contacts at England's Vickers armaments manufacturing company to help supply the Nationalists with weapons.

[51] One month before Hitler's annexation of Austria, known as the Anschluss, Canaris put the Abwehr into action and personally oversaw deception operations, which were designed to give the Austrians the impression of what appeared to be substantial German military preparations for an impending act of aggression.

[54] Among the first to arrive in Vienna, Canaris had a special team seize records from the Austrian archives since he feared possible references to his Spanish Civil War arms supplier connections in London.

[56] The most audacious plan contemplated by Canaris, in collaboration with Ewald von Kleist-Schmenzin, was to capture and to unseat Hitler and the entire Nazi Party before the invasion of Czechoslovakia.

The British declaration of war would have given the General Staff, it thought, both the pretext and the support for an overthrow of Hitler, which many of them were planning because of the prevailing "anti-war sentiment of the German people".

Hermann Göring fell out of favour with him for negotiating peace, but Hitler's drive for war remained unabated although the Western powers had granted him concessions.

[62] Canaris was relieved that war was averted and sought to re-establish contact with Hitler since many of the Abwehr reports submitted on the Sudeten crisis had proven to be grossly inaccurate.

[69] On 28 June 1941, after a two-year investigation, the FBI arrested Duquesne and 32 other Nazi spies on charges of relaying secret information on US weaponry and shipping movements to Germany.

On 2 January 1942, less than a month after the US attacked by Japan at Pearl Harbor and Germany had declared war on the United States, the 33 members of the Duquesne Spy Ring were sentenced to serve a total of more than 300 years in prison.

In a 1942 memo to his superiors, Canaris reported on the importance of several of his captured spies by noting their valued contributions, and he wrote that Duquesne had "delivered valuable reports and important technical material in the original, including U.S. gas masks, radio-controlled apparatus, leak proof fuel tanks, television instruments, small bombs for airplanes versus airplanes, air separator, and propeller-driving mechanisms.

[80] When the OKW decrees regarding the brutal treatment of Soviet prisoners of war related to the Commissar Order came to the attention of Canaris in mid-September 1941, he registered another complaint.

[85] A key piece of intelligence that passed from Canaris via Szymanska to the Allies was advance warning of the launch of Operation Barbarossa, the German invasion of the Soviet Union.

In Paris, he was conducted blindfolded to the Convent of the Nuns of the Passion of Our Blessed Lord, 127 Rue de la Santé, where he met the local head of the British Intelligence Services, codenamed "Jade Amicol", who was in reality Colonel Ollivier.

[108] No direct evidence of his involvement in the plot was discovered, but his close association with many of the plotters and certain documents written by him that were considered subversive led to the gradual assumption of his guilt.

[29] A prisoner claimed to have heard Canaris tap out a coded message on the wall of his cell on the night before his execution in which he denied he was a traitor and said that he had acted out of duty to his country.