With the First World War, these ententes were not military agreements - but they later involved the military because of the problems between the Triple Alliance and the Triple Entente. The Triple Entente became a military alliance. In 1915, Italy left the Triple Alliance, and from 1916 fought against Germany. The Russian revolution in October 1917 meant that Russia left the alliance, but the military alliance between France and the UK lasted until 1940, when Nazi Germanyinvaded France.
During World War I, Italy joined the Entente, declaring war against Austria–Hungary in May 1915, Turkey in August 1915, Bulgaria in October 1915, and Germany in August 1916. The alliance was expanded to create a multinational coalition, known as the "Allies".