Erwin von Witzleben was born in Breslau to a Thuringian family of old nobility and many officers. He completed the Prussian cadet corps program in Wahlstatt and Lichterfelde and on 22 June 1901 joined the Grenadier Regiment (König Wilhelm I) No. 7 in Liegnitz as lieutenant. In 1910, he was promoted to first lieutenant.

He was married to Else Kleeberg (who was born in Chemnitz, Saxony). The couple had a son and a daughter.

At the beginning of the First World War, von Witzleben served as brigade adjutant in the 19th Reserve Infantry Brigade, before he rose to captain and company chief in the Reserve Infantry Regiment no. 6 in October 1914. Later, in the same regiment, he became battalion commander. Von Witzleben's unit fought at Verdun, in the Champagne Region, and in Flanders, among other places. He was seriously wounded and was awarded the Iron Cross, both first and second classes. After being wounded, he went to General Staff Training and saw the war end as First General Staff Officer of the 121st Division.

In the Reichswehr, von Witzleben was taken on as a Company Chief. In 1923, he found himself on the Fourth Division staff in Dresden as a major. In 1928, he became battalion commander in Infantry Regiment No. 6 and retained that position as lieutenant colonel the following year. After being promoted to full colonel in 1931, he took over as head of Infantry Regiment No. 8 in Frankfurt (Oder). Early in 1933 came a transfer to the post of Infantry Leader VI in Hanover.

In the Wehrmacht, von Witzleben was promoted to major general on 1 February 1934 and moved to Potsdam as the new commander of the Third Infantry Division. He succeeded General Werner von Fritsch as Commander of Wehrkreis (Military District) III (Berlin). In this position, he was promoted to lieutenant general and in September 1935, became Commanding General of III Army Corps in Berlin. In 1936, he received his promotion to general of the infantry.

Even as early as 1934, von Witzleben had taken up a position against the Nazi regime when he and Erich von Manstein, Wilhelm von Leeb and Gerd von Rundstedt demanded an inquiry into Kurt von Schleicher's and Ferdinand von Bredow's deaths in the Night of the Long Knives. As a result of this and also his criticism of Adolf Hitler's persecution of General Werner von Fritsch, von Witzleben was forced into early retirement. His "retirement", however, did not last, as Hitler would later need von Witzleben upon the outbreak of war.

By 1938, von Witzleben belonged to the group of plotters around Colonel General Ludwig Beck, Generals Erich Hoepner and Carl - Heinrich von Stülpnagel, and Abwehr Chief Wilhelm Canaris. These men planned to overthrow Hitler in a military coup d'état, which seemed feasible at the time of the Sudeten Crisis in 1938. Von Witzleben's command, through the key Berlin Defense District, was to play a decisive role in the plan. However, Hitler's success in the Munich Agreement thwarted the conspirators' plans, and they were not put into operation.

Von Witzleben was likewise involved in Colonel General Kurt Freiherr von Hammerstein - Equord's 1939 conspiracy plans. Von Hammerstein - Equord planned to seize Hitler forthrightly, in a kind of frontal assault. It was to be von Witzleben's job to shut down Party Headquarters, but this plan also fell through.

Meanwhile, in November 1938, von Witzleben was posted as commander - in - chief of Army Group 2 to Frankfurt (Oder).

In September 1939, von Witzleben, now a colonel general, assumed command over the First Army, stationed in the West. When Germany attacked France on 10 May 1940, von Witzleben's army belonged to Army Group C. On 14 June, it broke through the Maginot Line, and within three days had forced several French divisions to surrender. For this, von Witzleben was decorated with the Knight's Cross of the Iron Cross, and on 19 July, he was promoted to Generalfeldmarschall. In 1941, he was appointed Commander - in - Chief West, but only a year later, he took his leave of this position for health reasons. Some sources, however, claim that he was forcibly retired at this time after criticizing the regime after Operation Barbarossa.

In 1944, the conspirators around Claus Graf Schenk von Stauffenberg saw Erwin von Witzleben as the key man in their plans. Whereas Colonel - General Beck was foreseen as provisional head of state and Colonel General Hoepner as Commander of the Ersatzheer ("Reserve Army"), Generalfeldmarschall von Witzleben was to take over supreme command of the whole Wehrmacht as the highest ranking German soldier. However on 20 July 1944, the day of von Stauffenberg's attempt on Hitler's life at the Wolf's Lair in East Prussia, von Witzleben did not arrive at the Bendlerblock in Berlin from the OKH - HQ (Oberkommando des Heeres Headquarters) at Zossen to assume command of the coup forces until 8.00pm when it was already clear that the coup attempt had failed. He then expressed anger that it had been bungled and left after 45 minutes to return to Zossen, where he reported the situation to General Eduard Wagner, after which he went to his country estate 30 miles away where he was arrested the next day by a General Linnertz.

He was then cast out of the Wehrmacht by the so-called Ehrenhof der Wehrmacht ("The Regular Army's Court of Honor"), a conclave of officers set up after the attempted assassination to remove officers from the Wehrmacht who had been involved in the plot, mainly so that they could be tried at the Volksgerichtshof rather than at a court martial.

On 7 August 1944, von Witzleben was in the first group of accused conspirators to be brought before the Volksgerichtshof. He approached the court making the Hitler's salute; this event has been completely ignored in writings about contemporary German history, although records exist they have been cut in versions for German and foreign public. In an attempt to humiliate Witzleben, he was made to appear before the court wearing trousers that were several sizes too big and, additionally, being denied a belt or suspenders, forcing him to continually hitch up trousers in court to prevent them from falling down. The presiding judge was Roland Freisler, who was notorious for ranting and belittling defendants in court. At one stage during the trial of von Witzleben, he bellowed "You dirty old man – stop fumbling with your trousers!". Later that same day, he sentenced Witzleben to death for his part in the plot. Von Witzleben's closing words in court – addressed to Freisler – were:

Much of the Volksgerichtshof, including scenes showing the trial of von Witzleben, was filmed for the German weekly newsreel, Die Deutsche Wochenschau; however, the Propaganda Ministry decided against releasing the footage, firstly because Freisler's conduct in the courtroom might draw sympathy for the accused, and secondly, because the regime wanted to quell public discussion of the event.

Erwin von Witzleben was put to death that same day at Plötzensee Prison in Berlin. He was hanged on a meat hook, with the execution filmed for Hitler's viewing.