The worlds will also have other factions placed in there automatically and they will have cities and units. On top of that there will be some neutral cities as well and you can stroll into those towns and take control. There will also be spawn points for monsters and by destroying them you prevent more enemies from spawning.
There will also be some resource tiles which enable you to do certain things so for example a pumpkin patch gives you access to build a pumpkin farm which gives you food which, when you have a surplus, lets your city grow. Silver lodes obviously allow for silver mines, etc. There are also resource tiles for mana which is necessary to cast spells.
Troops come from several sources. You automatically start with one city and two units. You can have your cities expand over time and create new units. You can capture cities of other races and then make their units, find and control wild animals and finally, you can summon units with certain spells.
