In this article I will give an assessment of why wars occur using research and personal knowledge. It is important to be able to define the term war before attempting to discover its causes and reasons. Wars have a long history in humanity and I believe it is important for people to understand the true definition of war and the main causes of past wars. This could, in a sense, aid humanity's understanding of the subject of war; it could also prevent future wars. The term war is defined in the Oxford Dictionary as “A state of armed conflict between different countries or different groups within a country:”, “A state of competition or hostility between different people or groups”, “A campaign supported against an undesirable situation. or activity.” Another more detailed definition of war is defined as “a state of conflict, usually armed, between two or more entities.” It is characterized by intentional violence on the part of a large number of individuals organized and trained for this purpose. (http://encyclopedia2.thefreedictionary.com/War) There are many reasons or theories as to why wars actually happen, so I did some research and found that "Heidelberg Institute for Research on international conflicts” gave several main causes. of war that seem general but apply to past and current wars. These causes are “ideological change, self-determination, national control, resources, territory, control of part of the country, control of another country”. These causes are very general, but I find it interesting because I think these entire categories can fit into one; change. I believe that, in a broader sense, all wars arise because of change. ...... middle of paper ...... lit or changed. There are wars motivated by economics, wars focused on patriotism and national pride, there are also wars that simply aim to eliminate ethnicities, religions or races. Yet, it is essential to understand all the theories and potential causes of war, as one must be able to identify these factors. A change in the balance of power, individuals' quest for power, or opposing interests and abilities can all be considered causes of war and the reason they occur. Of course, people can claim that the assassination of Archduke Francis Ferdinand was the cause of World War I, that Hitler was simply the cause of World War II, and these are all very broad answers and simple to the reasons why these wars took place. However, I am adamant that all wars have a reason and there is no simple explanation. After all, wars themselves are never simple.