This last period was primarily about the space race. A full space ship was launched as soon as it was ready. The second theme of the era was dealing with the rivals who were getting in the typical nasty mode of end game. Russians were conquered in this period and several Chinese cities were captured including their only coastal city to contain them. I could have wiped them out but the trade routes to their 4 remaining cities were too valuable and I decided containing them is fine. Sioux never attacked me despite placing units next to my cities. In one case I bribed the unit, in other cases they just withdrew. Expansion went on to the very end. The southern part of the map was fully covered but northern America and northern Asia had room for at least a dozen other cities. There was also plenty of unsettled space immediately north of the Himalayas. I ended with 143 cities.