Who was not invited to the Big Four peace talks?

The Big Four peace talks, which took place after World War I, primarily involved the leaders of the United States, the United Kingdom, France, and Italy. Notably absent from these discussions were the Central Powers, particularly Germany and Austria-Hungary, as well as Russia, which had exited the war following the Bolshevik Revolution. Additionally, smaller nations and some colonial territories were also not represented at these high-level negotiations.