Here is the full list of all 41 Sovereignty: Crown of Kings achievements.
You have learned 3 different 2nd Level Spells.
You have destroyed 1000 enemy Land Units.
You have 125,000 or more Gold in your Treasury.
You have called the Horde!
You have 50,000 or more Gold in your Treasury.
You have learned a 1st Level Spell.
You Unit has won 2 medals.
Your Unit has won a medal.
You are victorious in a named Battlefield.
You have attacked another province with a Stack of 20 Units.
You have hired a Hero.
You have successfully defended a province with 1 Unit remaining.
You have occupied a foreign Capitol and then retreated from it before it was destroyed.
You have had 100 trade offers accepted
You have forged 20 Alliances.
You have established 5 Cradles of Science.
You have established 5 Patron of the Arts.
You have cast Fading Age.
You have raised a Death Knight in defense of Old Hill!
You have captured 200 Prisoners.
You have destroyed 100 enemy Naval Units.
You have learned 6 different 3rd Level Spells.
You have learned 9 different 4th Level Spells.
You have learned 12 different 5th Level Spells.
You have played as 5 different Races.
You have 500,000 or more Gold in your Treasury.
You have destroyed 20 Human Realms.
You have destroyed 5 Orc Realms.
You have destroyed 5 Dwarven Realms.
You have destroyed 5 Elven Realms.
You have destroyed 5 Undead Realms
You are victorious in storyline campaigns of 5 different realms.
You are victorious in Conquest campaigns of 5 different Realms.
You are victorious in the Last Man Standing campaign of 5 different Realms.
You are victorious in the Rivalry campaign of 5 different Realms.
You are victorious in the Power Games campaign of 5 different Realms.
You are victorious in an Ironman campaign.
You are victorious in 10 Ironman campaigns.
You are victorious in Last Man Standing as Icespire.
You are victorious in Last Man Standing as Ladvia.
You are victorious in Last Man Standing as Crivia.