The Treaty of Versailles was the main peace treaty that ended World War I.

It was signed on June 28, 1919, exactly five years after the assassination of Archduke Franz Ferdinand.

The treaty was negotiated by the Allied powers, primarily the 'Big Four': the United States, Great Britain, France, and Italy.

Germany was not allowed to participate in the negotiations and was forced to sign the treaty.

A key and highly controversial part of the treaty was the 'War Guilt Clause' (Article 231), which forced Germany to accept sole responsibility for starting the war.

The treaty imposed severe reparations payments on Germany for war damages.

It also required Germany to disarm, drastically reducing the size of its army and navy, and demilitarizing the Rhineland.

Germany lost all of its overseas colonies and significant territory in Europe, including Alsace-Lorraine to France.

The treaty also established the League of Nations, an international peacekeeping organization.

The harsh terms of the treaty caused deep resentment in Germany and are considered by many historians to be a major long-term cause of World War II.