Battle of Ipsus (301 B.C.) - A very important battle during the Diadochi (Greek for "Successor" Wars).  After the death of Alexander the Great, his generals fought over his empire, and the Battle of Ipsus saw to it that no one general would dominate the others.  Antigonus Monophthalmus' power began to exceed that of his opponents, so the other generals allied with each other in order to insure that he could not become another Alexander.  The allied generals were victorious, and after the battle, the successor kingdoms began to take final shape.