The reason Boreal maps are a nightmare. The settings of the game were (I think): Huge, Boreal map type, Cylindrical wolrdwrap and standard resources. The entire world was a wasteland of forested tundra, with the occasional plains, intersected by huge areas of only ice. There were hardly any resources, apart from huge amounts of deers. During the Renaissance I started conquering, and I remember having 120 Deer late in the game.