Austria-Hungary was a multi ethnic state which meant that it was made up of people form many different nationalities. This caused problems when Nationalism took hold because all of the different groups of nationalities wanted their independence, they wanted national statehood. This caused turmoil and instability within the Empire.
Remember, at the time, it was the Austro-Hungarian Empire. The Empire (unlike any of the other major states in Europe) was a patchwork of over a dozen major ethnic groups. Nationalism tends to organize along ethnic boundaries (that is, nations tend to form around a large concentration of one ethnic group). Thus, with a very large number of different ethnic groups, the Empire had to worry about each group wanting to split from the Empire, and form its own nation.
Indeed, after WW1, this is what happened to the Empire - it was split into about a 8 different countries (or, more accurately, portions of 8 countries included lands formerly part of the Austro-Hungarian Empire).
Austria-Hungary was a multi ethnic state which meant that it was made up of people form many different nationalities. This caused problems when Nationalism took hold because all of the different groups of nationalities wanted their independence, they wanted national statehood. This caused turmoil and instability within the Empire.
nationalism
It is us the Filipino who is the most greatest threat of Filipino Nationalism
Constantinople was seen as a bulwark against an Islamic conquest of Europe. Its fall to the Ottomans meant that the Ottomans would soon conquer the Balkans and pose a direct threat to major Central and Eastern European States such as Russia, Poland, and the Austrian Empire.
If you are asking about WW I era it is the Balkans.
Ever since the early 1820s nationalism had been a threat to the Austrian Empire's very existence - first German nationalism, then Italian nationalism, Hungarian, Czech, Polish, Croat, Serbian, Romanian nationalism. In the years before WW1 Austria-Hungary was particularly concerned about Slav nationalism, which it saw as a vehicle for Russian influence and interference. In 1878 during a key stage in the break-up of the Ottoman Empire (in Europe) Bosnia-Herzegovina had been made an Austrian protectorate. In 1908 it looked briefly as if Turkey might become democratic and respectable and demand the area back. In an attempt to forestall this, Austria annexed the area outright. This infuriated Serb nationalists as they regarded Bosnia-Herzegovina as Serbian, though their claims then, as now, were weak.
They were a threat because the people could revolt and this could lead to the dissolution of the monarchy, if not counteracted.
Prussia, and with it the late German Empire. The only thing that "forced" them into an uneasy alliance was the "Entente" threat (mainly Russian and French threat). Prussia and Austria, due to common history in the Holy Roman Empire, had an endangered relation. The most important issue was the control over small duchies and kingdoms encompasing them. Prussia proved vital for securing their existence from outer threats, unlike the militarily weakened Austrian Empire.
Nationalism can take on various forms such as ethnic nationalism, civic nationalism, cultural nationalism, and religious nationalism. Each form emphasizes different aspects of a nation such as shared ancestry or culture, loyalty to the state, common traditions, or religious identity.
The ideas of Christianity were seen by many as a threat to the Roman Empire. Some believe that is why Rome eventually embraced Christianity, as to influence it.
The biggest threat was Napoleon, a long time enemy of the British Empire, who threatened to invade, but was finally defeated in 1815.
a protsetant rebellion in Spain
Speculative.