User blog comment:ProfessorMcG/Reworking of the Map Games/@comment-1650675-20100704010030

maybe you could have some technologies/government types,etc. that are "unlocked" at a certain point (ie nukes could be unlocked only at, say, 1940, a US-style democracy at 1700, flight at 1880, etc.) in order to make sure we don't have planes in 1550 (which is what happened in 1430 until Oerwinde rolled it back), and to ensure that nobody can completly wank out their nation.