Leaders and Cites is a modification for Rise of Nations and the expansion Thrones and Patriots. This mod simply adds more random leaders to fight against in Conquer the World mode as well as in a Single Player game. For instance, if you were fighting against the Americans in a Conquer the World game or a Single Player game, instead of facing George Washington or one of the presidents the game comes with, you might now be facing Ronald Reagan or Dwight D. Eisenhower, both additions in this mod. This same principle applies to the other nations included in this mod. It also adds randomly generated city names too. This means that when you build a city in any Single Player game mode, it will have a randomly generated name that was also not included in the original game.
This mod comes in different installments. Each installment will include new leaders for three nations and will include ten new city names. To check what installments have what, go to the installments section of the website. It will give you more details on that installment. Each installment will have later additions that will include new leaders as they come into power, and will include more cities not included in the original installment. To download any of the installments that are out, check the downloads section.