|Queen of Tristain|
|Reign||16 May 2010 - 15 July 2012|
|Predecessor||Marianne, Queen of Tristain|
Merged with the UK
|Sovereign Queen of Tristain-La Fontaine|
(After Union with the United Kingdom; Shared with Noctis Lucis Caelum)
|Reign||15 July 2012 - Present|
|Co-monarch||Noctis Lucis Caelum|
|Heir apparent||Louise de la Vallière, Countess of Ornières|
|Regent Lord||Saito Hiraga, Earl of Ornières|
|Born||16 August 1994|
Royal Capital of Tristania, Kingdom of Tristain
|Spouse||Ignis Stupeo Scientia|
|House||House of Tristain|
|Father||Henry III, King of Tristain|
|Mother||Marianne, the Queen Mother|
Henrietta (16 August 1994) is the current head of state of the Kingdom of Tristain-La Fontaine, the last monarch of the Kingdom of Tristain before it was merged with the Earldom of La Fontaine, creating the Kingdom as it is today. Henrietta is also the first Tristanian ruler to attain the title as the Sovereign Queen of Tristain-La Fontaine after the Act of Union 2012, when Tristain-La Fontaine was officially and formally united with the United Kingdom, resulting in the renaming of the name of the UK from the United Kingdom of Great Lucis and Accordo to the United Kingdom of Great Lucis and Tristain. Despite Tristain-La Fontaine's incorporation, Lucian King and Henrietta's close friend, Noctis Lucis Caelum insisted that she would remain as the sovereign ruler of Tristain-La Fontaine as well as having a separate parliament.
Henrietta played a vital role in securing her country's welfare and culture. She also prevented the Atlantic Federation's attempted aggression on Tristan-La Fontaine, which the Atlantic would use as a land for an invasion of the Lucis Isles. Despite it, she faced numerous republican, federal and imperial sentiments. Calls for the overthrow of the monarchy was called in 2012 after the union by the Tristanian Republican Movement. The six-day Tristanian Civil Coup of 2012 ensued but the attempt was foiled and Henrietta's prestige preserved. Today, Henrietta enjoys popular support from her countrymen.
Henrietta is also the youngest monarch to ascend the throne in 2009, overtaking King Noctis Lucis Caelum as the youngest monarch to ascend on the throne in the modern era at the age of just 16. Henrietta is married to the current Prime Minister of the United Kingdom, Ignis Stupeo Scientia since 2016. The marriage caused Henrietta to give the title of "Regent Minister" to her husband.