1867 The ''Ausgleich'' results in the establishment of the Dual Monarchy of Austria-Hungary.
1867 The Austro-Hungarian agreement known as Ausgleich ("the Compromise") is born through Act 12, which establishes the Austro-Hungarian Empire; on June 8 Emperor Franz Joseph is crowned King of Hungary.
1879 Germany and Austria-Hungary sign the "Twofold Covenant" and create the Dual Alliance.
1882 The Triple Alliance between Germany, Austria-Hungary and Italy is formed.
1889 Archduke Crown Prince Rudolf of Austria, heir to the Austro-Hungarian crown, is found dead with his mistress Baroness Mary Vetsera in Mayerling.
1914 Austria-Hungary issues an ultimatum to Serbia demanding Serbia to allow the Austrians to determine who assassinated Archduke Franz Ferdinand. Serbia will reject those demands and Austria will declare war on July 28.
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 Francis Ferdinand.
1914 World War I: the United Kingdom declares war on Austria-Hungary; the countries of the British Empire follow suit.
1915 World War I: Italy joins the Allies after they declare war on Austria-Hungary.
1915 World War I: Italy declares war on Austria-Hungary.
1916 World War I: Austrian sabotage causes the sinking of the Italian battleship ''Leonardo da Vinci'' in Taranto.
1916 Romania declares war against Austria-Hungary, entering World War I as one of the Allied nations.
1916 The Kingdom of Poland is proclaimed by the Act of November 5th of the emperors of Germany and Austria-Hungary.
1917 The first U.S. troops arrive in France to fight alongside Britain, France, Italy, and Russia against Germany, and Austria-Hungary in World War I.
1917 Battle of Caporetto; Italy suffers a catastrophic defeat at the forces of Austria-Hungary and Germany on the Austro-Italian front of World War I (lasts until 19 November - also called Twelfth Battle of the Isonzo).
1917 World War I: Battle of Caporetto; Italy suffers a catastrophic defeat at the forces of Austria-Hungary and Germany. The young unknown Oberleutnant Erwin Rommel captures Mount Matajur with only 100 Germans against a force of over 7000 Italians.
1917 World War I: The United States declares war on Austria-Hungary.
1918 World War I: Czechoslovakia is granted independence from Austria-Hungary marking the beginning of independent Czechoslovak state, after 300 years.
1918 Austria-Hungary enters into an armistice with the Allies, and the Habsburg-ruled empire dissolves.
1918 World War I: Austria-Hungary surrenders to Italy.