Surviving the Aftermath

Along with the other New Alliances achievements, I made separate save states in case something went wrong or I needed a different path such as to join the federation with 1 only embassy. Each society must be at 1000 reputation or close to it and have all tasks cleared. I built the first building on each society and then waited for all for to propose an alliance. I accepted all at the same time. I then paused the game, and placed all 5 embassies on the map, then un-paused. They will instantly build (no time needed) and unlock the achievement.