When you propose to start a new game of Imperialism 2, one of your options is to click the key on the table in the map room. The game invites you to "Enter a Map Generation Key" or to choose from one of twenty suggested "Pregenerated Map Keys".
The screen does not say whether any of them are specially designed (like Antarctica or Scotland, for example) or are truly random. However, each has been recently (in October 2014) superficially checked with a comparison with a map derived from another key with the same "value"; in each case, at least one of the nations had the same number of provinces, grain farms, open range, et al.
The list shows which 2, 3, 4, 5, or 6 nations the map derived from each key is good for. The little triangles at the top of each column let you sort by that column, e.g. to get all from your "most favored" nation at the top or to group the maps that are best for the number of players you plan to have in a multiplayer game.
|Key||Number of nations||England||France||Holland||Portugal||Spain||Sweden||notes|