There are actually several different conflicts that are taking place in the Middle East, and certainly more than two groups who are involved. Most conspicuously, there is the conflict between Arabs and Jews over the land of Israel/Palestine. But there is also a very serious conflict between Sunni Muslims and Shiite Muslims in diverse countries throughout the Middle East (like Lebanon, Iran, Iraq, etc.). There is a civil war in Syria, between supporters of Bashar al Assad and opponents of Bashar al Assad. There is a serious conflict between the Kurds of Iraq and their neighbors, especially Turkey. There are other conflicts as well, I am not going to list all of them.
Astolfo alludes to the conflict between the Christians and the Muslims during the Middle Ages, specifically the Crusades. This conflict was marked by religious and territorial disputes, leading to numerous military campaigns in the Holy Land. Astolfo's character often embodies the chivalric ideals associated with these conflicts.
Mediate is to be in the middle. A mediator sits between two parties.
Because there is no peace between them and not enough land and resources.
Conflicts between the Arabs and Israelis go back to biblical times. They have influenced the history of North Africa and the Middle East by having a constant state of conflict and unrest.
The same reason religious conflicts arise anywhere: because religious groups fight over their differences no matter where they are.
Mexico was in the middle of its Mexican Revolution (1910-1921).
Intolerance.
borders
I have not gotten into any conflicts in the Middle East and therefore there are no results to be had. If the question is asking about the results of the United States' involvement in Middle Eastern conflicts, please see the Related Question below.
conflicts for the middle colonies
Almost all of them have conflicts over water allocation. Specifically, Turkey, Syria, Iraq, Iran, Jordan, Lebanon, Israel, Palestine, Egypt, Sudan, and Morocco have the most violent and vitriolic disputes over water/
Almost all political systems in the Middle East have caused conflicts with the exception of liberal democracies (such as those in Israel or Turkey). However, the governments of both of those countries have fought in international conflicts.