World War

A world war is a military conflict affectingthe majority of the world's countries. World wars usually span multiple continents , and are very bloody and destructive.

The term is usually used to refer to World War I ( 1914 – 1918 ) and World War II ( 1939 – 1945 ).Both wars involved some degree of participation from most of the world's existing countries, specially through the colonial empires of GreatBritain , France , Germany , Italy and Japan , besides the United States and the SovietUnion .

Other wars in earlier periods that saw conflict across the world have been considered world wars by some, including the Seven Years' War ( 1756 – 1763 ; Winston Churchill called it "the first world war" in his A History of the EnglishSpeaking Peoples ), the French RevolutionaryWars ( 1792 – 1802 ) and the Napoleonic Wars ( 1803 – 1815 ).

There is some disagreement on whether there have been any world wars since 1945 ." World War III " was widely used to refer to a hypothetical nuclear warbetween the Soviet Union , the United States and their allies. " World War III " hasalso been used to refer to the Cold War ( 1945 – 1990 ) and to the War on Terrorism . " World War IV " was used byProfessor Eliot Cohen to refer to the War on Terrorism. However, these designations are not widely used.

Since the conclusion of World War I , called "the war to end all wars ," international organizations have been developedto prevent the outbreak of new wars. The League of Nations wasestablished after World War I , and collapsed with the outbreak of World WarII, after which the United Nations was formed.