Complex sentence: With the Treaty of Saint Germain, which regulated the dissolution of Austria-Hungary, the London Pact was nullified due to the efforts of American President Woodrow Wilson and the Slavic delegates, and Italian troops on the ground were soon joined by American and British forces.
Split into simpler sentences: With the Treaty of Saint Germain, which regulated the dissolution of Austria-Hungary, the London Pact was nullified due to the efforts of American President Woodrow Wilson and the Slavic delegates. Italian occupation troops on the ground were soon joined by American and British forces.