A Local Map surrounding the click area appears. The purple side bar shows information about the selected square. If it’s a city, it tells you the name of the city. If there are units stacked in the square, it displays the stack in a scrollable list below the terrain. I call this particular list the Stack List. The Fantastic War has, for all intents and purposes, no stacking limit per square, so go ahead and pile them in there (heh heh heh...). Your only restriction is that only units from one player may occupy one square at a time. Your side bar should look very much like mine if you hit that dark blue square just right. If not, click once on the blue Southerland Infantry unit on the map. In that scrollable list, practice clicking, shift-clicking, scrolling until you get the idea. You can also double-click and command-click units in that list but we'll get into those commands later.
Looking around in my game I see that there are no neutral units visible to me. I can only see units that are not mine if they're four squares from one of my cities or two squares from one of my units. Cities predominantly surrounded by one terrain are good bets for emissaries. So our first action will be to load up a caravan and scope out a few cities, but first lets check out some of the displays.