On the 2nd August 1934, the 86 year old German Reichspräsident Paul von Hindenburg died of lung cancer and Adolf Hitler became both the Führer and Reich Chancellor of the German People. It effectively merged the offices of both the President and Chancellor into one role, and therefore completed what the Nazis referred to as Gleichschaltung (or “Co-ordination”) by establishing Hitler as both Germany’s head of state and head of government.

Interfering with the post of President was illegal under the terms of the 1933 Enabling Act, and although Hitler merging the two positions removed any political checks and balances of his personal domination of Germany, a plebiscite held 17 days later on the 19th August saw an enormous 90% of people approving of the change.

Hitler’s assumption of the role of Führer also allowed the Nazi Party to more actively pursue its promotion of the ideology of Führerprinzip. This stated that Hitler possessed absolute control over the German government. Supported by a propaganda machine that relentlessly pushed the slogan Ein Volk, ein Reich, ein Führer – which translates as “One People, One Empire, One Leader” – the Führerprinzip also confirmed the Nazi Party’s complete control over every element of German society. This ranged from local government to factories and even to the management and control schools, although in terms of government it sometimes meant that officials were reluctant to make decisions without Hitler’s personal input or approval. It was also used by Nazi war criminals at the Nuremberg Trials to argue that they were not guilty since they were only following orders.

On the 26th July 1936, Adolf Hitler informed General Francisco Franco that Germany would support his Nationalist rebellion in Spain. Benito Mussolini, the leader of Italy, also agreed to intervene in the war on the Nationalist side after being encouraged to do so by Hitler. Although both countries later signed the Non-Intervention Agreement, they continued to send troops and equipment to support Franco’s forces.

The Spanish Civil War broke out on the 17th July, when an army uprising against the Spanish Second Republic that began in Morocco spread to the mainland. In the face of early rebel gains, the Republican government sought assistance from France and the USSR. Meanwhile the Nationalists turned to the right-wing governments of Germany and Italy.

Hitler in particular had a number of reasons for getting involved. As well as giving him the opportunity to take action against what he called “communist barbarism”, assisting Franco would win Germany an important ally and access to Spain’s natural resources. Militarily, German involvement also provided an opportunity to test the new equipment developed since the Nazi rearmament programme began in 1933.

Both Hitler and Mussolini were concerned about the risk of the Spanish Civil War escalating into a European-wide conflict, so at first their support for the Nationalists was small-scale and consisted mainly of transporting existing Spanish troops from Morocco to the mainland. However, as the war progessed their involvement grew. The German Condor Legion in particular began to take an active role in the aerial bombing of Republican areas, most notably the Basque town of Guernica, on the 26th April 1937.

On the 18th July 1925, the first volume of Adolf Hitler’s rambling racist manifesto Mein Kampf – which translates as My Struggle or My Battle – was first published. Dictated to his assistant Rudolf Hess whilst imprisoned in surprisingly luxurious conditions at Landsberg Prison, Mein Kampf laid out the blueprint for Hitler’s future plans for Germany, although when it was first published it gained little following outside the ranks of the Nationalist Socialist faithful.

In 1923, Hitler launched an attempted coup to seize power in Munich in Bavaria. Known as the Beer Hall Putsch, it ended in disaster for the Nazis when Hitler was arrested along with other Party leaders and charged with treason. Having been found guilty after a widely publicised 24-day trial, Hitler was sent to Landsberg as a nationally recognised figure.

Imprisonment gave Hitler time to reflect on the future direction of the Nazi Party and dictate Mein Kampf to Hess. It was in this book that Hitler clearly stated his anti-Semitic views, and attempted to justify his hatred. He also outlined his intentions for a future Germany including the destruction of the parliamentary system and the first reference to aggressive eastward expansion in order to gain Lebensraum “at the expense of Russia”.

Despite its initially poor reception, Mein Kampf became a popular book with hundreds of thousands of copies sold each year after Hitler became Chancellor of Germany in 1933, even though he increasingly distanced himself from it. Winston Churchill believed that, if world leaders had read it, they could have anticipated the full scale of Nazi domestic and foreign policy.

The 16th July 1945 marked the start of the atomic age when the USA detonated the first nuclear bomb under the codename ‘Trinity’. Nicknamed ‘the gadget’ by the people working on it, the plutonium-based weapon was detonated at the Alamogordo Test Range in New Mexico. The explosion was equivalent to about 20 kilotons of TNT, and the blast-wave was felt by civilians up to 160 miles away. To maintain secrecy, a press release was issued shortly after the successful detonation that claimed a large ammunition storage magazine had exploded.

The development of nuclear weapons by the US Army in the Manhattan Project that began in 1942 at Los Alamos Laboratory in New Mexico started due to concerns that Nazi Germany would develop an atomic bomb. By 1944 scientists had designed an implosion-type device and proposed that a test take place. The location was chosen in September, and an on-site laboratory was set up.

President Truman was keen to test the bomb before the Potsdam Conference began on the 18th July, so the 16th was chosen to give time to try again in case it failed. However when the appointed hour came rain was falling, which would have increased radioactive fallout, and so the detonation time was pushed back from 4am to 5.30am. At 5:29am the “the gadget” was exploded on top of a 100-foot steel tower, known as Point Zero. J. Robert Oppenheimer, the director of the Los Alamos Laboratory, later said that after the explosion he recalled a verse from Hindu scripture: ‘Now I am become Death, the destroyer of worlds.’

British naval ships attacked the French Navy at Mers-el-Kébir in Algeria during the Second World War.

On 22 June 1940 France and Nazi Germany signed the Second Armistice at Compiègne. This signalled the end of the Battle of France, and Britain was concerned that the significant naval force of the Marine Nationale would now pass to the pro-Nazi Vichy government. If these ships were used by the Axis powers, they would secure a significant advantage in the Battle of the Atlantic.

Winston Churchill received reassurances from Admiral François Darlan, commander of the French Navy, that the ships would remain under French control. However, Churchill and the War Cabinet were unwilling to risk the possibility that they might change hands.

Having decided that it was necessary to neutralise the French fleet, Operation Catapult was launched on 3 July. French ships in British ports were captured, while those at Mers-el-Kébir were offered an ultimatum by Force H under the command of Admiral Sir James Somerville. If the French didn’t surrender their ships or move them away from the reach of the Axis, they would be sunk.

Negotiations continued for much of the day, but at 5:54pm Churchill ordered the British ships to open fire in the first Anglo-French naval exchange since the Napoleonic Wars. The French were anchored in a narrow harbour that made them an easy target for the British guns. 1,300 French sailors were killed in just a few minutes, while one battleship was sunk with five more seriously damaged.

Churchill later recalled the ‘hateful decision, the most unnatural and painful in which I have ever been concerned’ but, in the context of the war, the attack at Mers-el-Kébir proved to the world that Britain was determined to keep fighting.

The 30th June 1934 saw the Nazis carry out a purge of their own party, when Hitler ordered the SS to murder leading figures of the SA or Brownshirts along with critics of the Nazi regime such as former chancellor von Schleicher. The purges actually went on throughout the weekend of the 30th June – 2nd July, even though the popular name suggests they only lasted for one night.

By the middle of 1934 Hitler was consolidating his rule over Germany but the relative autonomy of the SA within the Nazi Party was a concern. As Germany became a one-party state, the SA’s usual political targets for street violence were removed meaning that in a number of cases these representatives of the ruling party would instead intimidate civilians.

Such actions undermined the sense of order that Hitler was trying to project, and threatened to destabilise the party itself. The SA’s leader, Ernst Röhm, was a particular concern as he sought a so-called “second-revolution” to redistribute wealth within Germany in order to fulfil the socialist part of the Nationalist Socialist party’s name. Furthermore, the Reichswehr – Germany’s official army – were unhappy at Röhm’s desire to place the Reichswehr under the command of the SA.

On the morning of the 30th June, the homes of Röhm and other people who threatened Hitler’s power were broken into. While some were executed on the spot, others such as Röhm himself were held in prison for a few hours first. Hitler justified the purge in a public speech, claiming that he acted as “the supreme judge of the German people.”

On the 12th June 1942, Anne Frank received a diary as a thirteenth birthday present from her father. Barely three weeks later, Anne and her family went into hiding in Nazi-occupied Amsterdam. Her diary, which chronicled her experiences over the next two years, was published posthumously after the war under the title The Diary of a Young Girl and became one of the twentieth century’s most celebrated books.

The Frank family originated in Frankfurt, Germany, but moved away after the Nazi party won local elections in 1933. Anne’s father, Otto, was a businessman who chose to move the family to Amsterdam after receiving an offer to start a company there. However, when the German army invaded the Netherlands in 1940 the family found themselves trapped in a country subjected to anti-Semitic laws.

When, in July 1942, Anne’s older sister Margot was ordered by the Nazi authorities to go to a labour camp, their father instead arranged for the family to go into hiding in a so-called ‘Secret Annexe’ above his office building. It was here that Anne wrote her diary, which she addressed as Kitty. Over three volumes she recorded the relationships between the Frank family, the Van Pels family, and her father’s friend Fritz Pfeffer with whom they shared their confined hiding place.

An anonymous tip-off led to the discovery and arrest of the eight inhabitants on the 4th August 1944. They were deported to the Auschwitz concentration camp a month later. Anne died of typhus in early 1945 after being transferred to Bergen-Belsen. She was fifteen years old.

The 6th June 1944 saw the largest seaborne invasion in history, when the Allied forces of the Second World War launched Operation Neptune – more commonly known as the D-Day landings.  The amphibious landings in Normandy marked the start of the Allied invasion of Nazi-held Western Europe.

The invasion was focused on a 50-mile long stretch of Normandy coastline that had been divided into five codenamed sections known as Utah, Omaha, Gold, Juno and Sword beaches. German Field Marshall Erwin Rommel, nicknamed the Desert Fox for his leadership of Italian and German forces in the North African campaign, commanded the Nazi defence along what was known as the Atlantic Wall.

Prior to the landings, an airborne force of 24,000 Allied troops had been dropped behind enemy lines to seize or destroy features such as bridges, crossroads and key gun batteries. Despite this, the work of the first seaborne divisions was still difficult as they fought to clear the beaches under heavy fire from the numerous smaller gun emplacements that overlooked them. Rommel had previously identified the Normandy beaches as a possible invasion point and so had installed a range of obstacles such as wooden stakes, metal tripods, mines, and anti-tank devices that slowed down the Allied landing.

The Allies failed to achieve all their objectives on the first day and suffered at least 10,000 casualties. However, they did successfully establish a foothold on the continent that was gradually expanded over the next few months and led to the liberation of France and the defeat of the Nazis in the West.

Operation Dynamo, better known as the evacuation of Dunkirk, began.

Applauded by the British press as a heroic and miraculous rescue, Operation Dynamo saw an armada under the command of the Royal Navy successfully evacuate over 338,000 Allied troops from the beaches around the French port of Dunkirk.

The German army had invaded France on 10 May, and within just two weeks had cut off and surrounded a combined force of British, French and Belgian troops. Referred to by the recently-appointed British Prime Minister Winston Churchill as ‘a colossal military disaster’ the only hope was to retreat to the port of Dunkirk and evacuate as many soldiers as possible.

Operation Dynamo was overseen by Vice Admiral Bertram Ramsay who reputedly worked in a room within the cliffs of Dover that once housed an electrical dynamo, though there is no reliable evidence for this claim. The order to begin the operation was received at 18:57 on 26 May, less than a week after planning began.

The operation is famous for the flotilla of ‘little ships’ that sailed from Britain to assist the evacuation. Most of these were used to ferry soldiers from the beaches to the large navy ships that would sail across the Channel, although the majority of soldiers boarded ships directly from the stone and concrete mole that protected the harbour.

The evacuation took place amidst ferocious attacks from German aircraft and artillery. In response the Royal Air Force sent all available aircraft to protect the operation. Churchill later praised the fact that hundreds of thousands of soldiers had been evacuated from Dunkirk, but in a speech on 4 June needed to warn the public that ‘Wars are not won by evacuations.’

Josef Mengele, the Nazi ‘Angel Of Death’, was transferred to begin work at Auschwitz concentration camp.

Menegele had been a member of a right-wing paramilitary group that was absorbed into the Nazi SA in 1934. In 1937 he formally joined the Nazi Party and, the following year, began serving in the SS. By the start of 1943 Mengele had proved himself as both an effective medical officer in the field and a dedicated member of the Race and Resettlement Office.

Having developed an interest in the study of twins as part of his earlier genetics research, Mengele applied for a transfer to the concentration camp service. He was posted to Auschwitz-Birkenau on 24 May 1943 where he initially served as the chief physician in the Romani family camp.

As he moved up the ranks numerous sources record his delight in taking part in the “selections” that determined which prisoners were to be killed in the gas chambers and which were to be spared, as these often provided him with new subjects.

Mengele’s experiments involved such gruesome actions as injecting live subjects with chemicals, purposefully infecting people with diseases and, in one well-evidenced case, sewing two twins together in an attempt to create conjoined twins. Mengele was consequently responsible for the deaths of numerous victims thanks to his sadistic and barbaric actions.

Mengele was evacuated from Auschwitz in January 1945 and gradually moved West, escaping capture by the USSR. He was eventually taken as a prisoner of war by the Americans in June but, due a combination of factors, was later able to obtain false papers and flee to South America where he died, having evaded capture for war crimes, in 1979.