Of the many types of heroes in the Justice League, only one is truly king. Arthur Curry, ruler of Atlantis.
Despite this, him and Batman do have a very respectful relationship in the League. Batman respects Arthur's station, as well as the struggle he has to go through in order to maintain peace between Atlantis and the surface world. On the other side, Arthur respects Batman's skill, and though they sometimes fight over leadership, they usually end up on the same side of an argument.
Both have gotten on the others nerves, and both have struck at the other, but in the end, they've always put their prides aside in order to save the day.