World War I
Soon, most of Europe became involved. The Ottoman Empire (now Turkey) joined the war on the side of Germany and Austria-Hungary. It is not clear why the Ottomans entered the war, but they had become friendly to Germany. Italy had allied with Germany and Austria-Hungary but refused to help them since those countries had not been attacked first. Italy noted that Austria-Hungary had attacked Serbia first. Also, Italy had long disliked Austria-Hungary and wanted to take part of its land. It later joined the war for the Allies because they had promised land across the Adriatic Sea.