World War I began in 1914 after the assassination of Archduke Franz Ferdinand led to escalating tensions between allies. Major powers in Europe were divided into the Allied/Triple Entente powers including Britain, France, and Russia against the Central Powers of Germany and Austria-Hungary. Both sides had goals of defeating their enemies while avoiding a two-front war. The war quickly resulted in a bloody stalemate as new industrial weapons and tactics led to trench warfare on the Western Front. Over 65 million soldiers fought in the war and over 37 million casualties resulted before it ended in 1918.