The Austro-Hungarian Empire essentially collapsed in 1918. It had always possessed an unusually high number of ethnic groups and maintaining effective control over such a multi-cultural dominion had long been the great challenge of the Hapsburgs. In the last year of the war, this challenge became too much for them, as various ethnic peoples began assert their independence. In reality, there was little the Hapsburgs could do to stop them.

In addition, those same movements that had lead to the removal of Wilhelm II in Germany were growing more vocal in Austria as the war came to a close. On October 31 1918, even Hungary, fully one half of the Hapsburg empire (since every Austrian Emperor was also King of Hungary), severed its ties with the Austria.

It was in this context that, the last Hapsburg monarch, Charles I of Austria, took the only option that was left to him: he formally withdrew the monarchy from the affairs of the Austrian (November 11) and then Hungarian state (November 13). Soon after, he departed for Switzerland. Though this is generally considered the end of the rule of the House of Hapsburg-Lorraine, it is important to note that Charles did not abdicate. Indeed, his private correspondences revealed that he still considered himself the rightful ruler of both Austria and Hungary, which had transformed into the Republic of Germany-Austria and the Hungarian Democratic Republic respectively in response to Charles' proclamations.

The fact that Charles had left the country without having officially abdicated prompted the Austrian Parliament to pass the Hapsburg Law in April 1919, which effectively banished Charles and his family from Austria unless he formally abdicated and renounced his family's claim to the Austrian throne. If he did so, he and his family would be allowed to return to Austria as ordinary citizens.

Charles, scion of perhaps the oldest and most powerful House in European history that he was, utterly refused to admit defeat and spent the remaining three years of his life attempting to reclaim his thrones. Interestingly, in 1920, the Hungarian National Assembly voted to re-establish the Kingdom of Hungary. However, they recognised that the Allies would never accept the return of the Hapsburgs and instead installed Miklos Horthy as Regent of Hungary. A year later, the National Assembly voted to formally dethrone the Hapsburgs.

It wasn't until 1961 that Otto von Hapsburg, Charles' eldest son, officially renounced all Hapsburg claims to the throne of Austria. So ended the 800 year history of the House of Hapsburg.