Heads of state for victorious allies meet to discuss terms for defeated central powers. Main result was agreeing on terms for the Treaty of Versailles in that same year. Created primarily by the heads of state from France, the UK, the United States, as well as Italy- Georges Clemenceau, David Lloyd George, Woodrow Wilson, and Vittorio Emanuele Orlando, respectively.
Your class excludes Orlando, shortening the "Big Four" to the "Big Three", not sure why they do this, I guess they don't like Italy.
