The twentieth century was characterized by many notable events that left a mark in political, economic and social structure of nations, around the world. These events happened on the period dated January 1, 1901 and ended on December 31, 2000 (Goloboy, 2008). Among the most memorable events that left an impact in the sociological structure is war, industrialization, immigration and technological innovations. These events, with their impacts, have helped prepare for the twenty-first century. War has sadly been the most prominent occurrence of the twentieth century affecting the world. The First and Second World Wars had profound social effects. Soldier’s deployment to foreign lands and subjection to harsh environments during the war meant exposure to diseases such as pneumonia and tuberculosis. Veterans also suffered psychological effects from the war.