"Gentlemen, the Serbians have defiantly rejected our demands. They assassinated the heir to the empire and audaciously refused our requests, which clearly indicates that this assassination was a premeditated act by the Serbians. The empire must punish them, demonstrating the grave consequences of provoking us!" Marshal Conrad von Hötzendorf, Chief of the General Staff of the Austro-Hungarian Army, stated with palpable anger.
Emperor Franz Joseph I sat wearily upon his throne, lost in thought, contemplating the future of the war and the fate of the Austro-Hungarian Empire, or perhaps pondering who would inherit the title of heir following Archduke Ferdinand's assassination. After all, Franz Joseph I was now eighty-four years old, with little time remaining.
Other ministers and military leaders of the Austro-Hungarian Empire echoed the call for action, fervently believing that the time had come to annex Serbia and dominate the Balkan Peninsula, anticipating a glorious victory ahead.
"Friedrich, is the army fully prepared?" asked Franz Joseph I.
"Your Majesty, all six of our corps are ready for battle!" replied Archduke Friedrich.
As a nation of over fifty million, the Austro-Hungarian Empire could swiftly mobilize its army to exceed one million troops. However, among these forces, only a scant few possessed substantial combat effectiveness. The multitude of languages spoken among the diverse nationalities often left officers unable to comprehend their soldiers, who in turn struggled to grasp the officers' commands. Coupled with lax training and weak fighting spirit, it was unrealistic to expect such troops to possess formidable combat prowess.
Nevertheless, the rulers of the Austro-Hungarian Empire appeared oblivious to these challenges. They viewed Serbia merely as a small nation of three million. Even if all Serbians took up arms, they believed it could not match the unprepared forces of the Austro-Hungarian army.
"Your Majesty, according to our operational plan, if Russia does not engage the empire, three of our six corps will advance against Serbia, while two will stand guard against Russia, leaving one as a reserve. If Russia does declare war, we will send two corps to attack Serbia, three to defend against the Russians, and one will remain in reserve," Marshal Hötzendorf reported.
"Can our forces withstand a Russian assault?" Prime Minister Mario Weber expressed his concerns. Although Russia had recently suffered defeat at the hands of a smaller foe, its reputation as a military powerhouse remained intact.
"Russia indeed possesses considerable military strength, but we are not fighting alone. Should Russia dare to attack us, Germany will send reinforcements," Marshal Hötzendorf replied.
"Germany? Their main adversaries lie on the Western Front," remarked Baron Leopold von Berchtold, the Foreign Minister.
"Germany does not need to commit its main forces to the Eastern Front; a small contingent will sufficiently restrain a significant portion of the Russian army. Moreover, our mobilization continues. Soon, we will have ample troops to confront the Russians!" Archduke Friedrich asserted.
"Very well, gentlemen. Since the army is prepared and confident about the impending war, we must place our trust in them. Let us leave the rest to the military! The fate of the empire rests on this battle! God save the Austro-Hungarian Empire!" declared Franz Joseph I.
"God save the Austro-Hungarian Empire!" they all exclaimed in unison.
Emperor Franz Joseph I enjoyed immense respect within the empire; his decisions faced no opposition. He was the stabilizing force of the Austro-Hungarian Empire, ensuring its status as a powerful nation among the world's great powers. Yet, lamentably, with his advanced age, he had little time left. If the Austro-Hungarian Empire were to suffer defeat without a capable successor to uphold the realm, its imminent disintegration would loom large.
On July 28, the Austro-Hungarian government, citing Serbia's refusal to comply with its demands, officially declared war. The world war thus commenced, instigated by this declaration.
In response, Serbia sought assistance from the Russian Empire while simultaneously mobilizing its troops along the border to prepare for the impending Austro-Hungarian invasion.
However, the disparity in military strength was vast. Absent external support, Serbia stood little chance against the might of the Austro-Hungarian Empire.
Following the declaration of war, the Austro-Hungarian army, fully prepared, launched a large-scale offensive against Serbia. Uncertain of whether the Russian Empire would engage, the Austro-Hungarians initially deployed only two corps. Nevertheless, even this modest force proved overwhelming for Serbia.
The Russian Empire had long regarded Serbia as a protégé, supporting its expansion in the Balkans. The audacity of the Austro-Hungarian Empire to disregard Russian warnings and attack Serbia was intolerable to Tsar Nicholas II.
Under the Tsar's orders, the Russian Empire commenced full mobilization, with troops moving towards the border.
As an ally of the Russian Empire, France promptly began its own mobilization and troop movements.
Germany, an ally of the Austro-Hungarian Empire, recognizing the movements of Russia and France, issued a warning.
On July 31, Germany presented an ultimatum to Russia and France, demanding they cease mobilization. Germany threatened that should Russia intervene on behalf of Serbia, it would not hesitate to go to war. However, both Russia and France rejected Germany's demands, continuing their mobilizations. On the same day, Germany formally declared war on Russia, which in turn declared war on Germany, further escalating the scale of the conflict.