What's cool about it:

  An ingenious AI provides and maintains a unique strategic personality for each of the Major Powers.
  Cabinet Ministers assist you in various ways with advice and direction, depending on the difficulty level.
  Use the subtle art of diplomacy or the equally effective art of trade as you forge alliances or dominate your enemies.

Overview:

Do you have the necessary ambition and skills required to carve up underdeveloped nations and expand your countryΓÇÖs sphere of influence? Then go forth and conquer the world using any and all means available to you. Exploit the New World for its cornucopia of riches and resources as you race towards imperial supremacy over the entire world. You wonΓÇÖt be alone in your endeavors, however, as your Ministers are there to give useful advice whilst you retain the ultimate control over the fate of your nation and, eventually, the entire world.

Imperialism offers turn-based strategic gameplay in either a randomly generated world or in a scenario based on historic events. Choose from seven industrial powers including Great Britain, Hungary, Sardinia, Italy, Russia, and the Ottoman Empire and three different points of historical interest: the very beginnings of imperialism in 1820, in 1848 which was the year of tumultuous revolutions, or in 1882 and the nascent beginnings of the arms race that led up to the Great War. Take the reins of command and remake history as you dominate the world in Imperialism!

Minimum system requirements: 
Windows XP or Windows Vista, 1 GHz Processor (1.4 GHz recommended), 1 GB RAM (2 GB recommended), 3D graphics card compatible with DirectX 9, Mouse, Keyboard. 
http://www.gog.com/gamecard/imperialism