Our journey starts with an extremely promising omen. Here our car burns, and down there they will throw bombs at us. Archduke Franz Ferdinand comments wryly on the fact that his journey to Bosnia in June 1914 begins with his car overheating

The Archduke: Franz Ferdinand, the bumptious, little-loved 51-year-old nephew of the ailing Emperor Franz Joseph, was heir presumptive to the Austro-Hungarian throne. In 1913 he was made inspector general of the armed forces of Austria-Hungary; it was this role that took him to Bosnia in June 1914, to inspect the army’s summer manoeuvres.

The Duchess: Franz Ferdinand married Countess Sophie Chotek for love, for which both paid a price. She was from a Czech noble family but was deemed unfit to be a Habsburg bride; she had been a lady-in-waiting to Archduchess Isabella, whose sister Franz Ferdinand was expected to marry. Their marriage was morganatic, meaning their children were excluded from the line of succession. Although she was made Duchess of Hohenberg in 1909, the slights were constant at functions such as imperial banquets, where she had to enter the room last.

[Sophie] could never share [Franz Ferdinand’s] rank ... could never share his splendours, could never even sit by his side on any public occasion. There was one loophole ... his wife could enjoy the recognition of his rank when he was acting in a military capacity. Hence, he decided, in 1914, to inspect the army in Bosnia. There, at its capital Sarajevo, the Archduke and his wife could ride in an open carriage side by side ... Thus, for love, did the Archduke go to his death. AJP Taylor

The family: Three much-loved children, aged between 10 and 12 – Princess Sophie von Hohenberg (1901-1990), Maximilian, Duke of Hohenberg (1902-1962), Prince Ernst von Hohenberg (1904-1954); there was also a stillborn son (d. 1908). On the morning of his death, the Archduke sent a telegram to his children, congratulating Max on his recent exams.

The empire: 11 nationalities lived under the dual monarchy of Austria-Hungary, with as many grievances – 50 million people across modern-day Austria, Slovakia, the Czech Republic, Hungary, Croatia, Bosnia-Herzegovina, parts of Poland and northern Italy. Bosnia-Herzegovina was the most recent addition, having been annexed in 1908. Franz Ferdinand had opposed the annexation, not from any love for the southern Slavs, but as a pointless provocation of them and of Russia.

The grievance: The formal independence of Serbia had been recognised at the Congress of Berlin in 1878. Bosnian Serbs dreamt of joining it in a Greater Serbia. While Franz Ferdinand had no personal liking for the Serbs, he was not hostile to them: in fact he was thought to be a ‘federalist’ who supported giving more autonomy to Slavic lands. This alarmed the Serbs, who foresaw the creation of a third crown in the Austro-Hungarian empire with Zagreb the possible capital – if that happened the chances of creating Greater Serbia would vanish.

The targeting of the Archduke thus exemplified one abiding strand in the logic of terrorist movements, namely that reformers and moderates are more to be feared than outright enemies and hardliners.

Christopher Clark

The martyr: Bogdan Žerajić, a 22-year-old Serb medical student from Herzegovina, resolved to kill Emperor Franz Joseph at the opening of a new parliament in Sarajevo in June 1910. In the event, he fired at Marijan Varešanin, the governor of the province, missed, then killed himself with his final bullet. Vladimir Gaćinović, a driving force behind the liberation movement Mlada Bosna – Young Bosnia – wrote a pamphlet celebrating Žerajić and made a hero of him; his grave became a shrine. Among those inspired by his memory was Gavrilo Princip.

I often spent whole nights there, thinking about our situation, about our miserable conditions... and so it was that I resolved to carry out the assassination.

Gavrilo Princip, the eventual assassin, explains at his trial how he was drawn to Žerajić’s grave

The Black Hand: The annexation of 1908 helped radicalise Serb nationalist groups. On March 3 1911, in a Belgrade apartment, Ujedinjenje ili smrt! – Union or Death! – was formed, the secret society that came to be known as the ‘Black Hand’.

Gen Potiorek and Dragutin Dimitrijevic - 'Apis'

The plot: Just as they were intended to be, the details of the plot are difficult to nail down. The prime mover was Dragutin Dimitrijević, nicknamed ‘Apis’ (after the Egyptian bull god), 36-year-old head of Serbian military intelligence. In May 1903, he had led Serbian officers in overthrowing King Alexander I and his wife Queen Draga, who were murdered. The conspirators installed Peter I as the new king. Apis was present at the founding meeting of the Black Hand in 1911, as was his co-conspirator from 1903, Vojislav Tankosić, who was one of the handlers of the Sarajevo assassins.

Meanwhile Gaćinović, who had joined the Black Hand in 1912, instigated a plot to kill Gen Oscar Potiorek, governor of Bosnia-Herzegovina, in January 1914, but the would-be assassins' nerve failed. Planning now focused on the Archduke's visit to Sarajevo on June 28, rumours of which had circulated as early as autumn 1913.

The assassins: The three principal recruits were radicalised in the cafes of Belgrade by the Black Hand.

Trifko Grabež, Nedeljko Čabrinović and Gavrilo Princip

Trifko Grabež, 19, the son of an Orthodox priest in Pale, came to the city for his schooling.

Nedeljko Čabrinović, 19, who had left school at 14, went to Belgrade and found work with a printer.

Gavrilo Princip, 19, left Sarajevo in May 1912 for Belgrade after being expelled from school (where he had been with Grabež). He volunteered to join Serbian guerrillas fighting Ottoman Turks in the First Balkan War but was rejected as too weak and sickly. Princip’s interest extended beyond merely the Serb cause to the freedom of all southern Slavs.

I am a Yugoslav nationalist, aiming for the unification of all Yugoslavs, and I do not care what form of state, but it must be free from Austria.

Gavrilo Princip at his trial

Milan Ciganović, a Black Hand member and employee of Serbian state railways, was their handler; he reported to Tankosić who in turn reported to Apis. On May 27, Tankosić gave Princip and Čabrinović four Browning pistols and six small grenade-sized bombs from the Serbian State Arsenal, as well as cyanide powder with which to kill themselves after the assassination. Čabrinović was smuggled into Bosnia on May 30, Princip and Grabež followed on May 31.

The pistols used by the assassins, now in a museum in Vienna

They were joined in Sarajevo by a four-man cell recruited by Danilo Ilić, a Black Hand member aged 23. He had trained as a schoolteacher, and worked in Sarajevo as a proof-reader and the editor of a local paper. His recruits were:

Muhamed Mehmedbašić, 28, a Muslim carpenter from Herzegovina, who had been involved in the botched plan to kill Potiorek earlier in the year.

Cvjetko Popović, 18, was a school pupil in Sarajevo (he died in the city in 1980)

Vaso Čubrilović, 17, was also at school in Sarajevo and a member of Mlada Bosna, Young Bosnia.

The warnings: Serbian prime minister Nikola Pašić knew of the plot. If he did nothing and it succeeded, the Black Hand’s close relationship to the government would almost certainly be exposed; but an overt warning to Austria-Hungary would mark him as a traitor to many Serbs. So a veiled warning was sent to Vienna, via Dr Leon von Bilinski. the Austrian minister of finance, who was told that if Franz Ferdinand were to go to Sarajevo, ‘Some young Serb might put a live rather than a blank cartridge in his gun and fire it’. Bilinski rather missed the point: ‘Let us hope nothing does happen,’ he replied cheerfully.

The fateful day: Sunday June 28 1914 was St Vitus’s Day, the anniversary of the Battle of Kosovo on the ‘Field of Blackbirds’ in 1389, in which the Ottomans annihilated the Serbs. It remained a day of profound significance to all Serb nationalists.

It was also the 14th wedding anniversary of Franz Ferdinand and Sophie, a reminder of the day on which he had had to sign the Oath of Renunciation confirming that their children could not succeed to the imperial throne.

The day before had been cold and wet but the morning of June 28 was sunny. The couple had been staying outside Sarajevo at Ilidze for three days. So relaxed were they that they had come into Sarajevo two days before for a shopping trip, during which they were shadowed by Princip.

You are wrong after all... Everywhere we have gone here, we have been treated with so much friendliness – and by every last Serb, too – with so much cordiality and warmth that we are very happy about it

The Duchess to Dr Josip Sunaric, Bosnian Croat leader, the night before the assassination

The Archduke and the Countess arrive in Sarajevo by train

The couple were to drive in the second of a six-car motorcade from the railway station along the river to the City Hall. Danic and the six other would-be assassins were stationed along the route.

The car: a 32-horsepower, four-cylinder, open-topped Double Phaeton built in 1910 by the Viennese firm of Gräf & Sift. The numberplate was A III 118 – in which those who believe such things can see a portent of the eventual Armistice date in 1918.

The Archduke's car is now in a museum in Vienna

Franz Ferdinand and Sophie travelled with Gen Oscar Potiorek, the governor of Bosnia. Next to the driver in the front was Count Franz von Harrach, in charge of their security.

The royal party in the car

He wore: the dress uniform of a cavalry general – blue tunic, gold collar with three silver stars, black trousers with red stripe and a helmet with green peacock feathers.

She wore: white hat and veil, a long white silk dress with red and white fabric roses tucked into a red sash, and an ermine stole on her shoulders.

The first attempt: Mehmedbašić was the first of the young assassination team to be passed by the motorcade. As the Archduke’s car neared, he was about to throw his bomb but panicked.

Čabrinović, who was standing by river, was the first to act. He primed his bomb and threw it. The driver saw it coming and accelerated. It exploded beneath the car travelling behind the Archduke’s, the third in the motorcade, injuring several officers. A small splinter cut Sophie’s cheek.

Čabrinović swallowed his cyanide powder and jumped into the shallow waters of the river Miljacka. The poison didn’t work and he was arrested.

Come on, that fellow is clearly insane, let us proceed with our programme.

Franz Ferdinand reacts to the bomb

The remaining assassins lost their nerve. By the time the motorcade passed Princip it was moving too fast for him to shoot. Knowing that the party would return from City Hall later, he moved across to the right-hand side of Franz Joseph Street.

I didn’t pull out the revolver because I saw that the Duchess was there. I felt sorry for her

Vaso Čubrilović

The pause: At City Hall, the mayor of Sarajevo, Fehim Effendi Curcic, who had been in the first car, began a nervous speech of welcome. Franz Ferdinand interrupted, furiously: ‘I come here as your guest and you people greet me with bombs!’

The mayor was allowed to continue, then the Archduke spoke, the paper he held bearing the bloodstains of one of the officers in the third car. Having gathered himself, he praised the cheers of the people of Sarajevo, which he took to be an expression of relief at the failure of the assassination.

The couple leave City Hall

The change of plan: The motorcade was to have returned along Appel Quay and turned right into Franz Joseph Street, heading for the National Museum. But now the museum visit was cancelled; the route would be straight back back down Appel Quay. Franz Ferdinand wanted to visit Potiorek’s wounded adjutant in hospital. Originally, Sophie was to have gone to the governor’s palace while her husband went to the museum, but now she said she wished to accompany him.

No one told the drivers of the change of plan, so when the lead car in the motorcade turned right into Franz Joseph Street, the Archduke’s driver followed. Potiorek yelled that this was the wrong the way. The car was stopped and – without a reverse gear – it had to be pushed backwards.

The finale: Princip had been standing outside Moritz Schiller’s cafe on Franz Joseph Street. Now he ran forward, his pistol drawn. He paused on seeing the Duchess but fired twice at point-blank range. Whether he was lucky or whether his firearms training in Belgrade had paid off, both bullets hit their targets. The first went through the door of the car and hit Sophie in the abdomen; the second hit Franz Ferdinand in the neck. Harrach, aware of the continuing threat, had been travelling on the running board. Now he saw the Duchess slump across her husband, surely aware that both were dying, and heard the Archduke’s beseeching words to her:

Sopherl! Sopherl! Sterbe nicht! Bleibe am Leben für unsere Kinde! – Sophie, Sophie, don’t die, stay alive for our children!

As Princip prepared to kill himself his gun was knocked from his hands, as well as his packet of cyanide, as the crowd swarmed around him, kicking and punching; he was saved from probable death by his arrest.

Čabrinović arrested. Above, Princip after his capture

Franz Ferdinand and Sophie were rushed to the Konak palace. Shortly after 11am both were dead.

Franz Ferdinand and Sophie lying in state

The reaction:

The next morning, The Daily Telegraph began its leading article: 'A dark cloud of Fate seems to overhang the fortunes of the House of Habsburg... The circumstances are so peculiar that it is very difficult to understand the reasons for the crime or the exact motives of the murderer... His death is, we believe, a serious loss to Europe at large, as well as to Austria-Hungary herself... At a period when the world suffers from a lack of great personalities, the death of a man so strong and self-reliant as the Archduke Franz Ferdinand is a real disaster, of which it is difficult to overestimate the importance.'

The paper reported that news of the deaths was relayed to the aged emperor Franz Joseph at Ischl. 'I am spared nothing,' he is said to have murmured on hearing of the assassinations.

George V and Queen Mary were told the news by telegram from the British embassy in Vienna. They expressed their deep distress by return telegram. It was announced that the English Court would go into mourning for a week and a State Ball was cancelled.

Kaiser Wilhelm II was in Kiel inspecting German and British warships after the reopening of the canal. It was reported that at 5pm all the ships in the harbour hoisted the Austro-Hungarian flag at half mast, including the British warships.

Among German newspapers, the Berliner Tageblatt anticipated that 'the already sufficiently tense relationships of Austria-Hungary will undoubtedly be aggravated, even if no great Serbian conspiracy is demonstrable, and only Austrian subjects of Serbian nationality participated in the crime'.

In France, the Journal des Debats recognised that the Archduke's death was 'a European event of the highest political importance. The character of the late Archduke, the intentions that were ascribed to him, and his political and religious tendencies, caused it to be generally believed that his accession to power in the Dual Monarchy would be the signal of far-reaching changes'.

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Read the paper of 100 years ago at telegraph.co.uk/ww1archive