So, IRL Republics weren't allowed to become the Emperor, since it would be crazy to allow someone who's only going to rule for several years anyway to become the Emperor, and basically any Republican nations were made ineligible to attain the title. Now, I'm not sure what government type the Netherlands have IG, but IRL they were definitely a Republic and so should've started the game as a republic. I think I've even seen Canadian be called 'Stadtholder' a few times. I'm not here to try and make the Netherlands weaker, I'm actually pretty cordial with them, but if they're a republic it would make zero sense for their Stadtholder to become the Emperor.