That is to say, don't wait until after unlocking all the buildings from the previous Diplomatic rank before achieving 'The Sultan's confidante' if you want to start building the Sultan's mosque as soon as possible. It requires the highest Diplomatic rank, but only 1740 Envoys to unlock, while the final buildings from the previous Diplomatic rank are unlocked at 2600 Envoys. The Sultan's mosque is the only Oriental building that does not follow the linear progression between Oriental Inhabitants and Diplomatic rank.
The first step of constructing any Monument is to place the Foundation.
