At the same time, in October 1908, Austria-Hungary seized the opportunity of the Ottoman political upheaval to annex the de jure Ottoman province of Bosnia-Herzegovina, which it had occupied since 1878 ( see Bosnian Crisis ), and Bulgaria declared itself a fully independent kingdom.

In 1915, she joined the Entente powers and declared war on Austria-Hungary, and later Germany in the subsequent year.

Taking advantage of the Ottoman internal turmoil, Austria-Hungary annexed Bosnia and Herzegovina, and Bulgaria declared its independence from the Ottoman Empire.

Two years later, under the pressure of Allies ( especially France desperate to open a new front ), on August 14 / 27 1916 it joined the Allies, for which they were promised support for the accomplishment of national unity, Romania declared war on Austria-Hungary.

In August 1914, the German Empire declared war on France and Belgium, the UK declared war on Germany, and the UK and France declared war on Austria-Hungary.

Seeing this as a violation of the pre-war agreements, and discreetly encouraged by Germany and Austria-Hungary, Tsar Ferdinand declared war on Serbia and Greece and the Bulgarian army attacked on June 29.

When Serbia agreed to only eight of the ten demands, Austria-Hungary declared war on 28 July 1914.

The Bulgarians declared war on 14 October and the Kingdom was eventually overpowered by the joint forces of the German Empire, Austria-Hungary and Bulgaria in 1915.

The Kingdom of Italy had declared neutrality at the beginning of the war, officially because the Triple Alliance with Germany and Austria-Hungary was a defensive one, requiring its members to come under attack first.

The presence of the armies of Austria-Hungary to the south as well as initially those of Japan to the east limited Russia's involvement in the beginning ( however, Japan declared war on Germany on 23 August 1914 ).

Duan dissolved the parliament upon his return and declared war on Germany and Austria-Hungary on August 13, 1917.

On October 26 the government declared war on the Central Powers ; Germany, Austria-Hungary, and Ottoman Empire.

In 1914, Austria-Hungary declared war on Serbia, following the assassination of Archduke Franz Ferdinand of Austria, marking the start of the First World War.

Italy consequently declared war on Austria-Hungary on May 23, 1915.

The only country against which the United States has declared war more than once is Germany, against which the United States has declared war twice ( though a case could be made for Hungary as a successor state to Austria-Hungary ).

At the end of August 1916, the Romanian government, impressed by the early success of the Brusilov Offensive, declared war on Germany and Austria-Hungary.

Using the assassination and Serbian refusal as a pretext, Austria-Hungary declared war on Serbia on July 28, 1914 which was a beginning of World War I.

In 1917 Siam declared war on German Empire and Austria-Hungary, mainly to gain favour with the British and the French.

On the eve of the First World War, Drljević was the representative of the radical line demanding immediate and outright war with Austria-Hungary after it declared war on Serbia.

However, the " silesian nationality " ( Slonzaken Volk ) could only be declared in the region of Cieszyn ( before World War I part of Austria-Hungary ), while approximately 400, 000-500, 000 respondents from the other areas of East Upper Silesia, that before WWI were parts of Prussia, who declared " Upper Silesian nationality " ( Oberschlesier ), were assigned to German nationality category.

* 1916 – Romania declares war against Austria-Hungary, entering World War I as one of the Allied nations.

* 1916 – Romania declares war on Austria-Hungary, joining the Entente in World War I

* 1914 – World War I: the United Kingdom declares war on Austria-Hungary ; the countries of the British Empire follow suit.

The Great Powers, most notably France and Austria-Hungary, reacted to this diplomatic sensation by trying to dissuade the League from going to war, but failed.

In 1914, war broke out in Europe between Britain with allies and Germany, Austria-Hungary and later that year, the Ottoman Empire.

Austria-Hungary authorized the mobilization and the declaration of war against Serbia on 28 July 1914.

* France, not feeling ready for a war against Germany in 1912, took a totally negative position against the war, firmly informing its ally Russia that it would not take part in a potential conflict between Russia and Austria-Hungary if it resulted from the actions of the Balkan League.

As a result, Serbia was isolated militarily against its rival Austria-Hungary, a development that eventually doomed Serbia in the coming war a year later.

* 1917 – World War I: The United States declares war on Austria-Hungary.

The Dual Alliance was a defensive alliance between Germany and Austria-Hungary, which was created by treaty on October 7, 1879 as part of Bismarck's system of alliances to prevent / limit war.

Mussolini promoted the Italian intervention in the war as a revolutionary nationalist action to liberate Italian-claimed lands from Austria-Hungary.

The Italian Socialist Party opposed the war on the grounds of internationalism, but a number of Italian revolutionary syndicalists supported intervention against Germany and Austria-Hungary on the grounds that their reactionary regimes needed to be defeated to ensure the success of socialism.

Under the secret Treaty of London signed in April 1915, Triple Entente powers promised Italy that it would gain Vlorë ( Valona ) and nearby lands and a protectorate over Albania in exchange for entering the war against Austria-Hungary.

However, the war increased tension with Austria-Hungary, which also had ambitions in the region.

* 1914 – World War I: Austria-Hungary declares war on Serbia after Serbia rejects the conditions of an ultimatum sent by Austria on July 23 following the assassination of Archduke Franz Ferdinand.

* 1915 – World War I: Italy declares war on Austria-Hungary.

* 1915 – World War I: Italy joins the Allies after they declare war on Austria-Hungary.

The weapon that made these victories possible were the German Big Berthas and the Skoda 305 mm Model 1911 siege mortars, one of the best siege mortars of the war, on loan from Austria-Hungary.

Béla Bartók was born in the small Banatian town of Nagyszentmiklós in the Kingdom of Hungary, Austria-Hungary ( since 1920 Sânnicolau Mare, Romania ) on March 25, 1881.

Within two days following the assassination, Austria-Hungary and Germany advised Serbia that they should open an investigation, but Serbian Foreign Minister Gruic, speaking for Serbia replied, " Nothing had been done so far, and the matter did not concern the Serbian Government ," after which " high words " were spoken on both sides.

Masterspy Rade Malobabić, Serbian Military Intelligence's top agent against Austria-Hungary, was arrested on his return from Austria-Hungary after the assassination, but was also later released and given a commission running an army supply store.

* Austria-Hungary, struggling for a port on the Adriatic and seeking ways for expansion in the south at the expense of the Ottoman Empire, was totally opposed to any other nation's expansion in the area.

The Armistice with Austria-Hungary was signed in the Villa Giusti, near Padua, on November 3.

On one side were Germany, Austria-Hungary, the Ottoman Empire and Bulgaria ( the Central Powers / Triple Alliance ), while on the other side stood Serbia and the Triple Entente – the loose coalition of France, Britain and Russia, which were joined by Italy in 1915, Romania in 1916 and by the United States in 1917.

Berlin's analysis proved mistaken on every point, leading to Germany's increasing isolation and its dependence on the Triple Alliance, which brought together Germany, Austria-Hungary, and Italy.

Selye was born in Vienna, Austria-Hungary on 26 January 1907.

In the Act of 5th November 1916, the Kingdom of Poland ( Królestwo Regencyjne ) was recreated by Imperial Germany and Austria-Hungary on formerly Russian-controlled territory.

The day before his retirement he signed the offensive-defensive alliance with Germany, which placed the foreign relations of Austria-Hungary once more on a stable footing.

Josip Broz was born on 7 May 1892 in Kumrovec, in the northern Croatian region of Hrvatsko Zagorje in Austria-Hungary.

Gottwald, of ethnic German descent was born on 23 November 1896, in Deditz, Wischau, Moravia, Austria-Hungary ( now Vyškov, Czech Republic ).