The Winter Revolution was an internal conflict that took place in the Austro-Hungarian Empire, in December of 1917. It came on the heels of the disastrous defeat in the Third Balkan War, and resulted in the collapse of the Dual Monarchy, and the separation of Austria and Hungary into two separate nations.
In 1917, the Austro-Hungarian Empire was in dire straits. Their defeat in the Third Balkan War had shaken people's confidence in the Dual Monarchy. The standard of living had dived as people endured the hardships of war to fight the Russian Empire. Yet it seemed that it had all been for naught, as the Russians invaded the Empire itself, and crushed the Monarchy's armies in battle after battle.
The defeat in the war had left Austria-Hungary a nearly bankrupt nation. Most of their money had been spent raising armies to fight the Russians. Their people had reached nearly starvation levels, despite them being able to buy food from Germany and Italy. But the Italian entry into the war closed off that access to food, and the people were forced to continuing levels of poverty.
The problem was also inflamed by ethnic tensions. Continued defeat alienated the people, and they took out their frustration on each other. Violence continued a slow rise throughout the war between the various ethnic groups. Some came to their own conclusion, that the Austrians had led them down the path to defeat. Some in the Hungarian government decided that it would be better for them to be on their own.
Things came to a head on December 19. The winter had been especially cold, and the people were looking to the government for aid. But the government could not help them, due to a dearth of funds. The people were already angry with the government for having to give up so much to attain peace with Russia, and this drove them over the edge.
Protesters took to the streets, clamoring for government assistance, and for greater civil liberties. The protests came to an abrupt end as police fired into the crowds. Violence spread throughout the empire, as the protests spread. With the deployment of the police, the protests became violent as protesters clashed with police, and some police and army units defected to the side of the protesters.
People began actively clamoring for the overthrow of the monarchy and the establishment of a democracy.