1. Conflicts arise when people are competing for the same resources (such as territory, jobs and income, housing) when they aren't fairly distributed or when there aren't enough to go round. The same applies to natural resources (cultivable land, fresh water).
2. Conflicts arise when the people are unhappy with how they are governed. The most common conflicts occur when a particular group wants to be independent from a central government, or when their viewpoint isn't represented in the government, or when the government oppresses them and doesn't respect or meet their basic needs.
3. Conflicts arise when people's beliefs clash. Religious and political views are particularly sensitive, because people often depend on these for a sense of identity and belonging. Sometimes the conflict is caused by a religious/political group being attacked; sometimes it is because the group is eager to spread a particular belief and even enforce it on others. Some leaders may aggravate religious and political differences as part of their tactics for keeping or gaining power.
4. In the same way ethnic differences can cause conflict, or be made to cause it. Again, people's ethnicity gives them a sense of identity and belonging, and it is threats to this sense which can cause violent responses, just as individuals may lash out with angry words or gestures when they feel threatened.
Competition for resources is a big cause of war. This has something to do with supply and demand. When the demand for basic needs, opportunities is large and the supply of resources is scarce people will compete. This competition, most of times, leads to conflict. The conflict is also proportional to the discrepancy between the two factors. Examples of such are the civil wars in some African countries.
Corruption is another cause of war. People practice their right of suffrage because they